The following are examples of orders of magnitude for different lengths.
Contents
Detailed list
To help compare different orders of magnitude, the following list describes various lengths between
1.6
×
10
−
35
{\displaystyle 1.6\times 10^{-35}}
metres and
10
10
10
122
{\displaystyle 10^{10^{10^{122}}}}
metres. Metres are used in these tables to provide a common reference point, but metric prefixes above "k" are not commonly used with metres. So for example, 1.21 Gm would more commonly be written as 1.21 million km or (in scientific notation) 1.21 × 106 km. Interplanetary distances are also commonly measured in astronomical units. Distances on the interstellar or larger scale are typically measured in light-years or parsecs.
1 quectometre and less
The quectometre (SI symbol: qm) is a unit of length in the metric system equal to 10−30 metres.
To help compare different orders of magnitude, this section lists lengths shorter than 10−30 m (1 qm).
0 quectometres (0 meters) — gravitational singularity
1.6 × 10−5 quectometres (1.6 × 10−35 metres) – the Planck length (Measures of distance shorter than this do not make physical sense, according to current theories of physics.)
1 qm – 1 quectometre, the smallest named subdivision of the metre in the SI base unit of length, one nonillionth of a metre.
1 rontometre
The rontometre (SI symbol: rm) is a unit of length in the metric system equal to 10−27 metres.
10 rontometres
10 rm – the length of one side of a square whose area is one shed, a unit of target cross section used in nuclear physics
1 yoctometre
The yoctometre (SI symbol: ym) is a unit of length in the metric system equal to 10−24 metres.
2 ym – the effective cross-section radius of 1 MeV neutrinos as measured by Clyde Cowan and Frederick Reines.
1 zeptometre
The zeptometre (SI symbol: zm) is a unit of length in the metric system equal to 10−21 metres.
To help compare different orders of magnitude, this section lists lengths between 10−21 m and 10−20 m (1 zm and 10 zm).
2 zm – the upper bound for the width of a cosmic string in string theory.
2 zm – radius of effective cross section for a 20 GeV neutrino scattering off a nucleon
7 zm – radius of effective cross section for a 250 GeV neutrino scattering off a nucleon
10 zeptometres
To help compare different orders of magnitude, this section lists lengths between 10−20 m and 10−19 m (10 zm and 100 zm).
100 zeptometres
To help compare different orders of magnitude, this section lists lengths between 10−19 m and 10−18 m (100 zm and 1 am).
177 zm – de Broglie wavelength of protons at the Large Hadron Collider (7 TeV as of 2010)
1 attometre
The attometre (SI symbol: am) is a unit of length in the metric system equal to 10−18 metres.
To help compare different orders of magnitude, this section lists lengths between 10−18 m and 10−17 m (1 am and 10 am).
1 am – sensitivity of the LIGO detector for gravitational waves
1 am – upper limit for the size of quarks and electrons
10 attometres
To help compare different orders of magnitude, this section lists lengths between 10−17 m and 10−16 m (10 am and 100 am).
10–100 am – range of the weak force
86 am – charge radius of a Bottom eta meson
100 attometres
To help compare different orders of magnitude, this section lists lengths between 10−16 m and 10−15 m (100 am and 1 fm).
831 am – approximate proton radius
1 femtometre (or 1 fermi)
The femtometre (SI symbol: fm) is a unit of length in the metric system equal to 10−15 metres.
In particle physics, this unit is sometimes called a fermi, also with abbreviation "fm". To help compare different orders of magnitude, this section lists lengths between 10−15 metres and 10−14 metres (1 femtometre and 10 fm).
1 fm – diameter of a neutron, approximate range-limit of the color force carried between quarks by gluons
1.5 fm – diameter of the scattering cross section of an 11 MeV proton with a target proton
1.75 fm – the effective charge diameter of a proton
2.81794 fm – classical electron radius
3 fm – approximate range-limit of the nuclear binding force mediated by mesons
7 fm – the radius of the effective scattering cross section for a gold nucleus scattering a 6 MeV alpha particle over 140 degrees
10 femtometres
To help compare different orders of magnitude, this section lists lengths between 10−14 m and 10−13 m (10 fm and 100 fm).
1.75 to 15 fm – diameter range of the atomic nucleus
10 fm – the length of one side of a square whose area is one barn (10−28 m2), a unit of target cross section used in nuclear physics
30.8568 fm – 1 quectoparsec (10−30 parsecs)
100 femtometres
To help compare different orders of magnitude, this section lists lengths between 10−13 m and 10−12 m (100 fm and 1 pm).
570 fm – typical distance from the atomic nucleus of the two innermost electrons (electrons in the 1s shell) in the uranium atom, the heaviest naturally occurring atom
1 picometre
The picometre (SI symbol: pm) is a unit of length in the metric system equal to 10−12 metres (1/1000000000000 m = 0.000000000001 m).
To help compare different orders of magnitude this section lists lengths between 10−12 and 10−11 m (1 pm and 10 pm).
1 pm – distance between atomic nuclei in a white dwarf
1 pm – reference value of particle displacement in acoustics
2.4 pm – the Compton wavelength of an electron
5 pm – shorter X-ray wavelengths (approx.)
10 picometres
To help compare different orders of magnitude this section lists lengths between 10−11 and 10−10 m (10 pm and 100 pm).
25 pm – approximate radius of a helium atom, the smallest neutral atom
30.8568 pm – 1 rontoparsec
50 pm – Bohr radius: approximate radius of a hydrogen atom
~50 pm – best resolution of a high-resolution transmission electron microscope
60 pm – radius of a carbon atom
93 pm – length of a diatomic carbon molecule
96 pm – H–O bond length in a water molecule
100 picometres
To help compare different orders of magnitude this section lists lengths between 10−10 and 10−9 m (100 pm and 1 nm; 1 Å and 10 Å).
100 pm – 1 ångström
100 pm – covalent radius of sulfur atom
120 pm – van der Waals radius of a neutral hydrogen atom
120 pm – radius of a gold atom
126 pm – covalent radius of ruthenium atom
135 pm – covalent radius of technetium atom
150 pm – length of a typical covalent bond (C–C)
153 pm – covalent radius of silver atom
155 pm – covalent radius of zirconium atom
175 pm – covalent radius of thulium atom
200 pm – highest resolution of a typical electron microscope
225 pm – covalent radius of caesium atom
280 pm – average size of the water molecule
298 pm – radius of a caesium atom, calculated to be the largest atomic radius
340 pm – thickness of single layer graphene
356.68 pm – width of diamond unit cell
403 pm – width of lithium fluoride unit cell
1 nanometre
The nanometre (SI symbol: nm) is a unit of length in the metric system equal to 10−9 metres (1/1000000000 m = 0.000000001 m).
To help compare different orders of magnitude, this section lists lengths between 10−9 and 10−8 m (1 nm and 10 nm).
1 nm – diameter of a carbon nanotube
1 nm – roughly the length of a sucrose molecule, calculated by Albert Einstein
2.3 nm – length of a phospholipid
2.3 nm – smallest gate oxide thickness in microprocessors
3 nm – width of a DNA helix
3 nm – flying height of the head of a hard disk
3 nm – the average half-pitch of a memory cell manufactured circa 2022
3.4 nm – length of a DNA turn (10 bp)
3.8 nm – size of an albumin molecule
5 nm – size of the gate length of a 16 nm processor
5 nm – the average half-pitch of a memory cell manufactured circa 2019–2020
6 nm – length of a phospholipid bilayer
6–10 nm – thickness of cell membrane
6.8 nm – width of a hemoglobin molecule
7 nm – diameter of actin filaments
10 nanometres
To help compare different orders of magnitude this section lists lengths between 10−8 and 10−7 m (10 nm and 100 nm).
10 nm – shortest extreme ultraviolet wavelength or longest X-ray wavelength
10 nm – the average length of a nanowire
10 nm – lower size of tobacco smoke
10 nm – the average half-pitch of a memory cell manufactured circa 2016 –2017
13 nm – the length of the wavelength that is used for EUV lithography
14 nm – length of a porcine circovirus
14 nm – the average half-pitch of a memory cell manufactured circa 2013
15 nm – length of an antibody
18 nm – diameter of tobacco mosaic virus (Generally, viruses range in size from 20 nm to 450 nm.)
20 nm – length of a nanobe, could be one of the smallest forms of life
20–80 nm – thickness of cell wall in Gram-positive bacteria
20 nm – thickness of bacterial flagellum
22 nm – the average half-pitch of a memory cell manufactured circa 2011–2012
22 nm – smallest feature size of production microprocessors in September 2009
100 nanometres
To help compare different orders of magnitude, this section lists lengths between 10−7 and 10−6 m (100 nm and 1 μm).
100 nm – greatest particle size that can fit through a surgical mask
100 nm – 90% of particles in wood smoke are smaller than this.
120 nm – greatest particle size that can fit through a ULPA filter
120 nm – diameter of a human immunodeficiency virus (HIV)
120 nm – approximate diameter of SARS-CoV-2
125 nm – standard depth of pits on compact discs (width: 500 nm, length: 850 nm to 3.5 μm)
180 nm – typical length of the rabies virus
200 nm — typical diameter of the chickenpox virus
200 nm – typical size of a Mycoplasma bacterium, among the smallest bacteria
300 nm – greatest particle size that can fit through a HEPA (high efficiency particulate air) filter (N100 removes up to 99.97% at 300 nm, N95 removes up to 95% at 300 nm)
300–400 nm – near ultraviolet wavelength
400 nm – length of the capsid of a Mimivirus, one of the largest and most complex viruses.
400–420 nm – wavelength of violet light (see Color and Visible spectrum)
420–440 nm – wavelength of indigo light
1 micrometre (or 1 micron)
The micrometre (SI symbol: μm) is a unit of length in the metric system equal to 10−6 metres (1/1000000 m = 0.000001 m).
To help compare different orders of magnitude, this section lists some items with lengths between 10−6 and 10−5 m (between 1 and 10 micrometres, or μm).
~0.7–300 μm – wavelength of infrared radiation
1 μm – the side of a square of area 10−12 m2
1 μm – edge of cube of volume 10−18 m3 (1 fL)
1–10 μm – diameter of a typical bacterium
1 μm – length of a lysosome
1 μm – diameter of aerosol
1–2 μm – anthrax spore
2 μm – length of an average E. coli bacteria
3–4 μm – size of a typical yeast cell
5 μm – length of a typical human spermatozoon's head
6 μm – thickness of the tape in a 120-minute (C120) compact cassette
7 μm – diameter of the nucleus of a typical eukaryotic cell
about 7 μm – diameter of human red blood cells
3–8 μm – width of strand of spider web silk
5–10 μm – width of a chloroplast
10 micrometres
To help compare different orders of magnitude, this section lists lengths between 10−5 m and 10−4 m (10 μm and 100 μm).
10 μm – width of cotton fibre
10 μm – tolerance of the mold used to manufacture a Lego brick
10 μm – transistor width of the Intel 4004, the world's first commercial microprocessor
10 μm – mean longest dimension of a human red blood cell
5–20 μm – dust mite excreta
10.6 μm – wavelength of light emitted by a carbon dioxide laser
15 μm – width of silk fibre
17 μm – minimum width of a strand of human hair
17.6 μm – one twip, a unit of length in typography
10 to 55 μm – width of wool fibre
20 μm — diameter of a cloud droplet
25 μm — diameter of grass pollen
25.4 μm – 1/1,000 inch, commonly referred to as 1 mil in the U.S. and 1 thou in the U.K.
30 μm – length of a human skin cell
30.8568 μm – 1 zeptoparsec
50 μm – typical length of Euglena gracilis, a flagellate protist
50 μm – typical length of a human liver cell, an average-sized body cell
100 micrometres
To help compare different orders of magnitude, this section lists lengths between 10−4 m and 10−3 m (100 μm and 1 mm). The term myriometre (abbr. mom, equivalent to 100 micrometres; frequently confused with the myriametre, 10 kilometres) is deprecated; the decimal metric prefix myrio- is obsolete and was not included among the prefixes when the International System of Units was introduced in 1960.
100 μm – 1/10 of a millimetre
100 μm – 0.00394 inches
100 μm – smallest distance that can be seen with the naked eye
100 μm – average diameter of a strand of human hair
100 μm – thickness of a coat of paint
100 μm – length of a dust particle
120 μm – the geometric mean of the Planck length and the diameter of the observable universe: √8.8 × 1026 m × 1.6 × 10−35 m
120 μm – diameter of a human ovum
139 µm - the size of Dicopomorpha echmepterygis, the smallest insect
170 μm – length of the largest mammalian sperm cell (rat)
170 μm – length of the largest sperm cell in nature, belonging to the Drosophila bifurca fruit fly
181 μm – maximum width of a strand of human hair
100–400 μm – length of Demodex mites living in human hair follicles
175–200 μm – typical thickness of a solar cell.
1 millimetre
The millimetre (SI symbol: mm) is a unit of length in the metric system equal to 10−3 metres (1/1000 m = 0.001 m).
To help compare different orders of magnitude, this section lists lengths between 10−3 m and 10−2 m (1 mm and 1 cm).
1.0 mm – 1/1,000 of a metre
1.0 mm – 0.03937 inches or 5/127 (exactly)
1.0 mm – side of a square of area 1 mm²
1.0 mm – diameter of a pinhead
1.5 mm – average length of a flea
2 mm — diameter of an average rain droplet
2.54 mm – distance between pins on old dual in-line package (DIP) electronic components
5 mm – length of an average red ant
5 mm – diameter of an average grain of rice
5.56×45 mm NATO – standard ammunition size
6 mm – approximate width of a pencil
7 mm – length of a Paedophryne amauensis, the smallest-known vertebrate
7 mm – length of a human tooth
7.1 mm – length of a sunflower seed
7.62×51 mm NATO – common military ammunition size
8 mm – width of old-format home movie film
1 centimetre
The centimetre (SI symbol: cm) is a unit of length in the metric system equal to 10−2 metres (1/100 m = 0.01 m).
To help compare different orders of magnitude, this section lists lengths between 10−2 m and 10−1 m (1 cm and 1 dm).
1 cm – 10 millimetres
1 cm – 0.39 inches
1 cm – edge of a square of area 1 cm2
1 cm – edge of a cube of volume 1 mL
1 cm – length of a coffee bean
1 cm – approximate width of average fingernail
1.2 cm – length of a bee
1.2 cm – diameter of a die
1.5 cm – length of a very large mosquito
1.6 cm – length of a Jaragua Sphaero, a very small reptile
1.7 cm – length of a Thorius arboreus, the smallest salamander
1.77 cm – approximate diameter of a black hole the mass of earth.
2 cm – approximate width of an adult human finger
2 cm – upper bound of the length of the largest bacteria, the Thiomargarita magnifica.
2.4 cm – diameter of a human eye
2.54 cm – 1 inch
1 decimetre
The decimetre (SI symbol: dm) is a unit of length in the metric system equal to 10−1 metres (1/10 m = 0.1 m).
To help compare different orders of magnitude, this section lists lengths between 10 centimetres and 100 centimetres (10−1 metre and 1 metre).
Conversions
10 centimetres (abbreviated to 10 cm) is equal to:
1 decimetre (dm), a term not in common use (1 L = 1 dm3.)
100 millimetres
3.9 inches
a side of a square of area 0.01 m2
the edge of a cube with a volume of 1×10−3 m3 (1 L)
Wavelengths
10 cm = 1.0 dm – wavelength of the highest UHF radio frequency, 3 GHz
12 cm = 1.2 dm – wavelength of the 2.45 GHz ISM radio band
21 cm = 2.1 dm – wavelength of the 1.4 GHz hydrogen emission line, a hyperfine transition of the hydrogen atom
100 cm = 10 dm – wavelength of the lowest UHF radio frequency, 300 MHz
Human-defined scales and structures
10 cm = 1 dm — length of a kazoo instrument
10.16 cm = 1.016 dm – 1 hand used in measuring height of horses (4 inches)
12 cm = 1.2 dm – diameter of a compact disc (CD) (120 mm)
9-12 cm = 0.9-1.2 dm — average height of a soda can
15 cm = 1.5 dm – length of a Bic pen with cap on
20 cm = 2 dm — height of a water bottle
22 cm = 2.2 dm – diameter of a typical association football (soccer ball)
30 cm = 3 dm – typical school-use ruler length (300 mm)
30.48 cm = 3.048 dm – 1 foot (measure)
60 cm = 6 dm – standard depth (front to back) of a domestic kitchen worktop in Europe (600 mm)
60 cm = 6 dm — diameter of the LAGEOS satellite
90 cm = 9 dm – average length of a rapier, a fencing sword
91 cm = 9.1 dm — length of a shopping cart
91.44 cm = 9.144 dm – one yard (measure)
Nature
10 cm = 1 dm – diameter of the human cervix upon entering the second stage of labour
11 cm = 1.1 dm – length of an average potato in the U.S.
13 cm = 1.3 dm – body length of a Goliath birdeater
18.1 cm = 1.81 dm – Maximum overall length of the Hercules beetle, one of the largest beetle species
19 cm = 1.9 dm — length of an average male human hand
19 cm = 1.9 dm – length of a banana
20 cm = 2 dm — diameter of the Syringammina, one of the largest single-celled organisms
20 cm = 2 dm - average height of the Venus flytrap
26.3 cm = 2.6 dm – length of an average male human foot
29.98 cm = 2.998 dm – distance light in vacuum travels in one nanosecond
30 cm = 3.0 dm – maximum leg length of a Goliath birdeater
31 cm = 3.1 dm – wingspan of largest butterfly species Ornithoptera alexandrae
32 cm – length of the Goliath frog, the world's largest frog
46 cm = 4.6 dm – length of an average domestic cat
46 cm = 4.6 dm – skull length of a Kelenken, a terror bird
50 to 65 cm = 5 to 6.5 dm – a coati's tail
Astronomical
84 cm = 8.4 dm – approximate diameter of 2008 TS26, a meteoroid
1 metre
To help compare different orders of magnitude, this section lists lengths between one metre and ten metres.
Light, in vacuum, travels 1 metre in 1⁄299,792,458, or 3.3356409519815E-9 of a second.
Conversions
1 metre is:
10 decimetres
100 centimetres
1,000 millimetres
39.37 inches
3.28 feet
1.1 yards
side of square with area 1 m2
edge of cube with surface area 6 m2 and volume 1 m3
radius of circle with area π m2
radius of sphere with surface area 4π m2 and volume 4/3π m3
Human-defined scales and structures
1 m – approximate height to the top part of a doorknob on a door
1 m – diameter of a very large beach ball
1 m – height of a typical washing machine
1.29 m – length of the Cross Island Chapel, the smallest church in the world
1.4 m – length of a Peel P50, the world's smallest car
1.4 m – length of a pool noodle
1.435 m – standard gauge of railway track used by about 60% of railways in the world = 4 ft 81⁄2 in
1.5 m – height of the Lasko pedestal fan
1.8 m – height of an average refrigerator
1.9 m – height of a vending machine
2 m – typical height of an average door
2.5 m – distance from the floor to the ceiling in an average residential house
2.7 m – length of the Starr Bumble Bee II, the smallest plane
2.77–3.44 m – wavelength of the broadcast radio FM band 87–108 MHz
2.8 m – height of a telephone booth
3.05 m – the length of an old Mini
6 m – height of an average typical house
Sports
2.44 m – height of an association football goal
2.45 m – highest high jump by a human (Javier Sotomayor)
3.05 m – (10 feet) height of the basket in basketball
8.95 m – longest long jump by a human (Mike Powell)
Nature
1 m – length of Rafflesia arnoldii, the largest flower in the world
1 m – height of Homo floresiensis (the "Hobbit")
1 m — length of an ocelot, a type of cat
1.06 m — length of a goat
1.1 m — length of a pig
1.15 m – a pizote (mammal)
1.5 m – height of an okapi
1.5 m — height of an orangutan
1.63 m – (5 feet 4 inches, or 64 inches) – height of average US female human as of 2002
1.75 m – (5 feet 8 inches) – height of average US male human as of 2002 (source: US Centers for Disease Control and Prevention)
1.8 m — height of a gorilla
2 m — height of a kangaroo
2.1 m – average height of a moose, the largest type of deer
2.4 m – wingspan of a mute swan
2.5 m – height of a sunflower
2.5 m – average length of a black mamba, the second longest venomous snake and the longest venomous snake in Africa
2.7 m – length of a leatherback sea turtle, the largest living turtle
2.72 m – (8 feet 11 inches) – tallest-known human (Robert Wadlow)
Astronomical
3 to 6 m – approximate diameter of 2003 SQ222, a meteoroid
4.1 m – diameter of 2008 TC3, a small asteroid that flew into the Earth's atmosphere on 7 October 2008
1 decametre
The decametre (SI symbol: dam) is a unit of length in the metric system equal to 10 metres (101 m).
To help compare different orders of magnitude, this section lists lengths between 10 and 100 metres.
Conversions
10 metres (very rarely termed a decametre which is abbreviated as dam) is equal to:
10 metres
100 decimetres
1,000 centimetres
10,000 millimetres
10,000,000 micrometres (or rarely 10,000,000 microns)
32.8 feet
11 yards
side of a square with area 100 m²
Human-defined scales and structures
10 metres – wavelength of the highest shortwave radio frequency, 30 MHz
10.2 metres – length of the Panzer VIII Maus, the world's largest tank
12 metres – height of the Newby-McMahon Building, the world's littlest skyscraper
12 metres — length of a school bus and city bus
16 metres — length of a semi-truck
23 metres – height of Luxor Obelisk, located in the Place de la Concorde, Paris, France
25 metres – wavelength of the broadcast radio shortwave band at 12 MHz
29 metres – height of the Savudrija Lighthouse
30 metres – height of Christ the Redeemer
31 metres – wavelength of the broadcast radio shortwave band at 9.7 MHz
32 metres – length of one arcsecond of latitude on the surface of the Earth
33.3 metres – height of the De Noord, the tallest windmill in the world
34 metres – height of the Split Point Lighthouse in Aireys Inlet, Victoria, Australia
40 metres – rotorspan of the Mil Mi-26, the largest helicopter
40 metres – average depth beneath the seabed of the Channel tunnel
Sports
11 metres – approximate width of a doubles tennis court
15 metres – width of a standard FIBA basketball court
15.24 metres – width of an NBA basketball court (50 feet)
18.44 metres – distance between the front of the pitcher's rubber and the rear point of home plate on a baseball field (60 feet, 6 inches)
20 metres – length of cricket pitch (22 yards)
27.43 metres – distance between bases on a baseball field (90 feet)
28 metres – length of a standard FIBA basketball court
28.65 metres – length of an NBA basketball court (94 feet)
49 metres – width of an American football field (531⁄3 yards)
59.436 metres – width of a Canadian football field (65 yards)
70 metres – typical width of an association football field
91 metres – length of an American football field (100 yards, measured between the goal lines)
Nature
10 metres – average length of human digestive tract
12 metres – height of a standard saguaro cactus
12 metres – moderate length of a whale shark, largest living fish
12 metres – wingspan of a Quetzalcoatlus, a pterosaur
12 metres – length of a Sarcosuchus, the largest crocodile ever
12.8 metres – length of a Titanoboa, the largest snake to have ever lived
13 metres – approximate length of a giant squid and colossal squid, the largest living invertebrates
13 metres – length of a Tyrannosaurus, the most popular dinosaur
14 metres – typical length of a Whale shark, the largest fish today
15 metres – approximate distance the tropical circles of latitude are moving towards the equator and the polar circles are moving towards the poles each year due to a natural, gradual decrease in the Earth's axial tilt
16 metres – length of a sperm whale, the largest toothed whale
17 metres – length of an average-sized Megalodon, widely considered to be the largest shark to ever roam the waters
18 metres – height of a Sauroposeidon, the tallest-known dinosaur
18 metres – maximum length of Spinosaurus, the largest land-living carnivore ever existed
Astronomical
30.8568 metres – 1 femtoparsec
11 metres – diameter of 1998 KY26, a rapidly spinning asteroid
1 hectometre
The hectometre (SI symbol: hm) is a unit of length in the metric system equal to 100 metres (102 m).
To compare different orders of magnitude this section lists lengths between 100 metres and 1,000 metres (1 kilometre).
Conversions
100 metres (sometimes termed a hectometre) is equal to:
327.9 feet
one side of a 1 hectare square
a fifth of a modern li, a Chinese unit of measurement
the approximate distance travelled by light in 300 nanoseconds
Human-defined scales and structures
100 metres – wavelength of the highest medium wave radio frequency, 3 MHz
100 metres – spacing of location marker posts on British motorways
103 metres – length of the Spearhead-class expeditionary fast transport
109 metres – width of the International Space Station
110 metres – height of the Saturn V
122 metres – height of the Starship v1, the tallest rocket currently under development by SpaceX
138.8 metres – height of the Great Pyramid of Giza (Pyramid of Cheops)
139 metres – height of the world's former tallest roller coaster, Kingda Ka
140 metres – height of the SpaceX's Starship v3.
157 metres – height of the Cologne Cathedral
162 metres – height of the Ulm Minster, the tallest church building in the world
162 metres – height of the Falcon's Flight, the tallest roller coaster as of May 2026.
165 metres – height of the Dushanbe Flagpole, the tallest flagpole from May 2011 to September 2014
169 metres – height of the Washington Monument
171 metres – height of the Jeddah Flagpole, the tallest flagpole from September 2014 to December 2021
Sports
100 metres – the distance a very fast human can run in about 10 seconds
100.584 metres – length of a Canadian football field between the goal lines (110 yards)
91.5 metres – 137 metres – length of a soccer field
105 metres – length of football pitch (UEFA stadium categories 3 and 4)
105 metres – length of a typical football field
109.73 metres – total length of an American football field (120 yards, including the end zones)
110 to 150 metres – the width of an Australian football field
135 to 185 metres – the length of an Australian football field
137.16 metres – total length of a Canadian football field, including the end zones (150 yards)
Nature
115.5 metres – height of the world's tallest tree in 2007, the Hyperion sequoia
310 metres – maximum depth of Lake Geneva
340 metres – distance sound travels in air at sea level in one second; see Speed of sound
947 metres – height of the Tugela Falls, the highest waterfall in Africa
979 metres – height of the Angel Falls in Venezuela, the world's highest free-falling waterfall
Astronomical
270 metres – length of 99942 Apophis
535 metres – length of 25143 Itokawa, a small asteroid visited by a spacecraft
1 kilometre
The kilometre (SI symbol: km) is a unit of length in the metric system equal to 1000 metres (103 m).
To help compare different orders of magnitude, this section lists lengths between 1 kilometre and 10 kilometres (103 and 104 metres).
Conversions
1 kilometre (unit symbol km) is equal to:
1,000 metres
0.621371 miles
1,093.61 yards
3,280.84 feet
39,370.1 inches
100,000 centimetres
1,000,000 millimetres
Side of a square of area 1 km2
Radius of a circle of area π km2
Human-defined scales and structures
1 km – wavelength of the highest long wave radio frequency, 300 kHz
1.008 km – proposed height of the Jeddah Tower, a megatall skyscraper under construction in Saudi Arabia
1.280 km – span of the Golden Gate Bridge (distance between towers)
1.609 km – 1 statute mile
1.852 km – 1 nautical mile, equal to 1 arcminute of latitude at the surface of the Earth
1.991 km – span of the Akashi Kaikyō Bridge
2.309 km – axial length of the Three Gorges Dam, the largest dam in the world located in China
3.991 km – length of the Akashi Kaikyō Bridge, longest suspension bridge in the world as of December 2008
4 km – width of Central Park
5.072 km – elevation of Tanggula Mountain Pass, below highest peak in the Tanggula Mountains, highest railway pass in the world as of August 2005
5.8 km – elevation of Cerro Aucanquilcha, highest road in the world, located in Chile
98 airports have paved runways from 4 km to 5.5 km in length.
8 km – length of Palm Jebel Ali, an artificial island built off the coast of Dubai
9.8 km – length of The World, an artificial archipelago that is also built off the coast of Dubai, whose islands resemble a world map
Nature
1.5 km – distance sound travels in water in one second
Geographical
1.637 km – deepest dive of Lake Baikal in Russia, the world's largest freshwater lake
2.228 km – height of Mount Kosciuszko, highest point on mainland Australia
Most of Manhattan is from 3 to 4 km wide.
3.776 km – height of Mount Fuji, highest peak in Japan
4.478 km – height of Matterhorn
4.509 km – height of Mount Wilhelm, highest peak in Papua New Guinea
4.810 km – height of Mont Blanc, highest peak in the Alps
4.884 km – height of Carstensz Pyramid, highest peak in Oceania
4.892 km – height of Mount Vinson, highest peak in Antarctica
5.610 km – height of Mount Damavand, highest peak in Iran
5.642 km – height of Mount Elbrus, highest peak in Europe
5.895 km – height of Mount Kilimanjaro, highest peak in Africa
6.081 km – height of Mount Logan, highest peak in Canada
6.190 km – height of Denali, highest peak in North America
6.959 km – height of Aconcagua, highest peak in South America
7.5 km – depth of Cayman Trench, deepest point in the Caribbean Sea
Astronomical
1 km – diameter of 1620 Geographos
1 km – very approximate size of the smallest-known moons of Jupiter
1.4 km – diameter of Dactyl, the first confirmed asteroid moon
4.8 km – diameter of 5535 Annefrank, an inner belt asteroid
5 km – diameter of 3753 Cruithne
5 km – length of PSR B1257+12
8 km – diameter of Themisto, one of Jupiter's moons
8 km – diameter of the Vela Pulsar
8.6 km – diameter of Callirrhoe, also known as Jupiter XVII
9.737 km – length of PSR B1919+21
10 kilometres (1 myriametre)
To help compare different orders of magnitude, this section lists lengths between 10 and 100 kilometres (104 to 105 metres). The myriametre (sometimes also spelled myriometre; 10,000 metres) is a deprecated unit name; the decimal metric prefix myria- (sometimes also written as myrio-) is obsolete and was not included among the prefixes when the International System of Units was introduced in 1960.
Conversions
10 kilometres is equal to:
10,000 metres
About 6.2 miles
1 mil (the Scandinavian mile), now standardized as 10 km:
1 mil, the unit of measure commonly used in Norway and Sweden used to be 11,295 m in Norway and 10,688 m in Sweden.
farsang, unit of measure commonly used in Iran and Turkey
Sports
42.195 km – length of the marathon
Human-defined scales and structures
18 km – cruising altitude of Concorde
27 km – circumference of the Large Hadron Collider, as of May 2010 the largest and highest energy particle accelerator
34.668 km – highest manned balloon flight (Malcolm D. Ross and Victor E. Prather on 4 May 1961)
38.422 km – length of the Second Lake Pontchartrain Causeway in Louisiana, U.S.
39 km – undersea portion of the Channel tunnel
53.9 km – length of the Seikan Tunnel, as of October 2009, the longest rail tunnel in the world
77 km – rough total length of the Panama Canal
Geographical
10 km – height of Mauna Kea in Hawaii, measured from its base on the ocean floor
11 km – deepest-known point of the ocean, Challenger Deep in the Mariana Trench
11 km – average height of the troposphere
14 km – width of the Strait of Gibraltar
21 km – length of Manhattan
22 km – narrowest width of the Cook Strait between New Zealand's main islands
23 km – depth of the largest earthquake ever recorded in the United Kingdom, in 1931 at the Dogger Bank of the North Sea
34 km – narrowest width of the English Channel at the Strait of Dover
50 km – approximate height of the stratosphere
90 km – width of the Bering Strait
Astronomical
10 km – diameter of the most massive neutron stars (3–5 solar masses)
13 km – mean diameter of Deimos, the smaller moon of Mars
20 km – diameter of the least massive neutron stars (1.44 solar masses)
20 km – diameter of Leda, one of Jupiter's moons
20 km – diameter of Pan, one of Saturn's moons
20 km – diameter of the Crab Pulsar.
22 km – diameter of Phobos, the larger moon of Mars
27 km – height of Olympus Mons above the Mars reference level, the highest-known mountain of the Solar System
30.8568 km – 1 picoparsec
43 km – diameter difference of Earth's equatorial bulge
66 km – diameter of Naiad, the innermost of Neptune's moons
100 kilometres
A length of 100 kilometres (about 62 miles), as a rough amount, is relatively common in measurements on Earth and for some astronomical objects.
It is the altitude at which the FAI defines spaceflight to begin.
To help compare orders of magnitude, this section lists lengths between 100 and 1,000 kilometres (105 and 106 metres).
Conversions
A distance of 100 kilometres is approximately 62 miles (or 62.137 miles exactly).
Human-defined scales and structures
100 km – the Kármán line: the internationally recognized boundary of outer space
105 km – distance from Giridih to Bokaro
109 km – length of High Speed 1 between London and the Channel Tunnel
130 km – range of a Scud-A missile
163 km – length of the Suez Canal
164 km – length of the Danyang–Kunshan Grand Bridge
213 km – length of Paris Metro
217 km – length of the Grand Union Canal
223 km – length of the Madrid Metro
300 km – range of a Scud-B missile
386 km – altitude of the International Space Station
408 km – length of the London Underground (active track)
460 km – distance from London to Paris
470 km – distance from Dublin to London as the crow flies
600 km – range of a Scud-C missile
600 km – height above ground of the Hubble Space Telescope
804.67 km – distance of the Indy 500 automobile race (500 miles)
Geographical
42 km – width of Singapore
75 km – width of Rhode Island
111 km – distance covered by one degree of latitude on Earth's surface
120 km – width of Brunei
180 km – distance between Mumbai and Nashik
200 km – width of Qatar
203 km – length of Sognefjorden, the third-largest fjord in the world
220 km – distance between Pune and Nashik
240 km – width of Rwanda
240 km – widest width of the English Channel
400 km – width of West Virginia
430 km – length of the Pyrenees
450 km – length of the Grand Canyon
500 km – widest width of Sweden from east to west
501 km – width of Uganda
550 km – distance from San Francisco to Los Angeles as the crow flies
560 km – distance of Bordeaux–Paris, formerly the longest one-day professional cycling race
590 km – length of land boundary between Finland and Sweden
724 km – length of the Om River
Astronomical
100 km – the altitude at which the FAI defines spaceflight to begin
167 km – diameter of Amalthea, one of Jupiter's inner moons
200 km – width of Valles Marineris
220 km – diameter of Phoebe, the largest of Saturn's outer moons
300 km – the approximate distance travelled by light in one millisecond
340 km – diameter of Nereid, the third-largest moon of Neptune which has a highly elliptical orbit
350 km – lower bound of Low Earth orbit
420 km – diameter of Proteus, the second-largest moon of Neptune
468 km – diameter of the asteroid 4 Vesta
472 km – diameter of Miranda, one of Uranus's major moons
974.6 km – greatest diameter of 1 Ceres, the largest Solar System asteroid
1 megametre
The megametre (SI symbol: Mm) is a unit of length in the metric system equal to 1000000 metres (106 m).
To help compare different orders of magnitude, this section lists lengths starting at 106 m (1 Mm or 1,000 km).
Conversions
1 megametre is equal to:
1000 km
106 m (one million metres)
approximately 621.37 miles
Human-defined scales and structures
2.100 Mm – length of proposed Iran-Pakistan-India gas pipe
2.100 Mm – distance from Casablanca to Rome
2.288 Mm – length of the official Alaska Highway when it was built in the 1940s
2.688 Mm – distance from Point Nemo, the farthest place anyone could get from any land, to the closest point of land, Easter Island
3.069 Mm – length of Interstate 95 (from Houlton, Maine, to Miami, Florida)
3.846 Mm – length of U.S. Route 1 (from Fort Kent, Maine, to Key West, Florida)
5.000 Mm – width of the United States
5.007 Mm – estimated length of Interstate 90 (Seattle, Washington, to Boston, Massachusetts)
5.614 Mm – length of the Australian Dingo Fence
6.371 Mm – global-average Earth radius
6.4 Mm – length of the Great Wall of China
7.821 Mm – length of the Trans-Canada Highway, the world's longest national highway (from Victoria, British Columbia, to St. John's, Newfoundland)
8.836 Mm – road distance between Prudhoe Bay, Alaska, and Key West, Florida, the endpoints of the U.S. road network
8.852 Mm – aggregate length of the Great Wall of China, including trenches, hills and rivers
Sports
The Munda Biddi Trail in Western Australia, Australia, is over 1,000 km long – the world's longest off-road cycle trail
1.200 Mm – the length of the Paris–Brest–Paris bicycling event
Several endurance auto races are, or were, run for 1,000 km:
Bathurst 1000
1000 km Brands Hatch
1000 km Buenos Aires
1000 km Donington
1000 km Monza
1000 km Nürburgring
1000 km Silverstone
1000 km Spa
1000 km Suzuka
1000 km Zeltweg
Geographical
1.010 Mm – distance from San Diego to El Paso as the crow flies
1.100 Mm – length of Italy
1.200 Mm – length of California
1.200 Mm – width of Texas
1.500 Mm – length of the Gobi Desert
1.600 Mm – length of the Namib, the oldest desert on Earth
2.000 Mm – distance from Beijing to Hong Kong as the crow flies
2.300 Mm – length of the Great Barrier Reef
2.800 Mm – narrowest width of Atlantic Ocean (Brazil-West Africa)
2.850 Mm – length of the Danube river
2.205 Mm – length of Sweden's total land boundaries
2.515 Mm – length of Norway's total land boundaries
3.690 Mm – length of the Volga river, longest in Europe
4.000 Mm – length of the Kalahari Desert
4.350 Mm – length of the Yellow River
4.600 Mm – width of the Mediterranean Sea
4.800 Mm – length of the Sahara
4.800 Mm – widest width of Atlantic Ocean (U.S.-Northern Africa)
5.100 Mm – distance from Dublin to New York as the crow flies
Astronomical
1.000 Mm – estimated shortest axis of triaxial dwarf planet Haumea
1.186 Mm – diameter of Charon, the largest moon of Pluto
1.280 Mm – diameter of the trans-Neptunian object 50000 Quaoar
1.340 Mm – diameter of the trans-Neptunian object Makemake
1.436 Mm – diameter of Iapetus, one of Saturn's major moons
1.578 Mm – diameter of Titania, the largest of Uranus's moons
2.122 Mm – estimated longest axis of Haumea
2.326 Mm – diameter of the dwarf planet Eris, the most massive trans-Neptunian object found to date
2.376 Mm – diameter of Pluto
2.442 Mm – estimated diameter of Earth's Core.
2.707 Mm – diameter of Triton, largest moon of Neptune
3.122 Mm – diameter of Europa, the smallest Galilean satellite of Jupiter
3.476 Mm – diameter of Earth's Moon
3.643 Mm – diameter of Io, a moon of Jupiter
4.821 Mm – diameter of Callisto, a moon of Jupiter
4.879 Mm – diameter of Mercury
5.150 Mm – diameter of Titan, the largest moon of Saturn
10 megametres
To help compare different orders of magnitude, this section lists lengths starting at 107 metres (10 megametres or 10,000 kilometres).
Conversions
10 megametres (10 Mm) is
6,215 miles
side of a square of area 100,000,000 square kilometres (km2)
radius of a circle of area 314,159,265 km2
Human-defined scales and structures
11.085 Mm – length of the Kyiv-Vladivostok railway, a longer variant of the Trans-Siberian Railway
13.300 Mm – length of roads rehabilitated and widened under the National Highway Development Project (launched in 1998) in India
39.000 Mm – length of the SEA-ME-WE 3 optical submarine telecommunications cable, joining 39 points between Norden, Germany, and Okinawa, Japan
53.800 Mm — length of the BNSF Railway
67.000 Mm – total length of National Highways in India
80.000 Mm – 20,000 (metric, French) leagues (see Jules Verne, Twenty Thousand Leagues Under the Seas)
100.000 Mm — height of a Space elevator
Geographical
10 Mm – approximate altitude of the outer boundary of the exosphere
10.001 Mm – length of the meridian arc from the North Pole to the Equator (the original definition of the metre was based on this length)
40.000 Mm – length of the Ring of Fire
60.000 Mm – total length of the mid-ocean ridges
Astronomical
12.000 Mm — diameter of AR Scorpii, largest pulsar ever discovered
12.000 Mm – diameter of Sirius B, a white dwarf
12.104 Mm – diameter of Venus
12.742 Mm – diameter of Earth
12.900 Mm – minimum distance of the meteoroid 2004 FU162 from the centre of Earth on 31 March 2004, closest on record
14.000 Mm – smallest diameter of Jupiter's Great Red Spot
19.000 Mm – separation between Pluto and Charon
30.8568 Mm – 1 nanoparsec
34.770 Mm – minimum distance of the asteroid 99942 Apophis on 13 April 2029 from the centre of Earth
35.786 Mm – altitude of geostationary orbit
40.005 Mm – polar circumference of the Earth
40.077 Mm – equatorial circumference of the Earth
49.528 Mm – diameter of Neptune
51.118 Mm – diameter of Uranus
100 megametres
To help compare different orders of magnitude, this section lists lengths starting at 108 metres (100 megametres or 100,000 kilometres or 62,150 miles).
102 Mm – diameter of Smertrios (HD 149026 b), an unusually dense Jovian planet
115 Mm – width of Saturn's Rings
120 Mm – diameter of EBLM J0555-57Ab, the smallest-known red dwarf
120 Mm – diameter of Saturn
142 Mm – diameter of Jupiter, the largest planet in the Solar System
146 Mm – diameter of WISE 0855–0714, the coldest known brown dwarf
170 Mm – diameter of TRAPPIST-1, a star discovered to have seven planets around it
170,5 Mm – diameter of SIMP0136, a rogue planet with auroral activity
174 Mm – diameter of OGLE-TR-122b, one of the smallest known stars
180 Mm – average distance covered during life
204,6 Mm – diameter of PSO J318.5–22 – a rogue planetary-mass object
215 Mm – diameter of Proxima Centauri, the nearest star to the Solar System
257 Mm – diameter of TrES-4b, one of the largest exoplanets
260 Mm – diameter of the Barnard's Star
1 gigametre
The gigametre (SI symbol: Gm) is a unit of length in the metric system equal to 1000000000 metres (109 m).
To help compare different distances this section lists lengths starting at 109 metres (1 gigametre (Gm) or 1 billion metres).
1.2 Gm – separation between Saturn and Titan
1.39 Gm – diameter of Sun
1.5 Gm – orbit from Earth of the James Webb Space Telescope
1.71 Gm – diameter of Alpha Centauri A, one of the closest stars.
2.19 Gm – closest approach of Comet Lexell to Earth, happened on 1 July 1770; closest comet approach on record
2.38 Gm – diameter of Sirius A, brightest naked eye star.
3 Gm – total length of "wiring" in the human brain
3.5 Gm – diameter of Vega
4.2 Gm – diameter of Algol B
4.3 Gm – circumference of Sun
5.0 Gm – closest approach of Comet Halley to Earth, happened on 10 April 837
5.0 Gm – (proposed) Size of the arms of the giant triangle shaped Michelson interferometre of the Laser Interferometer Space Antenna (LISA) planned to start observations sometime in the 2030s.
7.9 Gm – diameter of Bellatrix, a blue dwarf or blue giant
10 gigametres
To help compare different distances this section lists lengths starting at 1010 metres (10 gigametres (Gm) or 10 million kilometres, or 0.07 astronomical units).
10.4 Gm – diameter of Spica, an oval-shaped blue giant star and a nearby supernova candidate.
12.6 Gm – diameter of Pollux, the closest red giant star to the Sun. It is a red clump star fusing helium into carbon at its core.
15 Gm – closest distance of Comet Hyakutake from Earth
18 Gm – one light-minute (see yellow sphere in right-hand diagram)
24 Gm – radius of a heliostationary orbit
30.8568 Gm – 1 microparsec
35 Gm – approximate diameter of Arcturus, a close red giant star. It is on the red giant branch, fusing hydrogen into helium in a shell surrounding an inert helium core.
46 Gm – perihelion distance of Mercury (yellow ellipse on the right)
55 Gm – 60,000-year perigee of Mars (last achieved on 27 August 2003)
58 Gm – average passing distance between Earth and Mars at the moment they overtake each other in their orbits
61 Gm – diameter of Aldebaran, a red giant branch star (large star on right)
70 Gm – aphelion distance of Mercury
76 Gm – Neso's apocentric distance; greatest distance of a natural satellite from its parent planet (Neptune)
100 gigametres
To help compare distances at different orders of magnitude this section lists lengths starting at 1011 metres (100 gigametre or 100 million kilometres or 0.7 astronomical units).
103 Gm (0.69 au) – diameter of Rigel
109 Gm (0.7 au) – distance between Venus and the Sun
149.6 Gm (93.0 million mi; 1.0 au) – average distance between the Earth and the Sun – the original definition of the astronomical unit
163 Gm (1.09 au) – diameter of Deneb, a blue supergiant
228 Gm (1.5 au) – distance between Mars and the Sun
255 Gm (1.7 au) – diameter of Enif, a small red supergiant star in the constellation Pegasus
511 Gm (3.4 au) – average diameter of Mira, a pulsating red giant and the progenitor of the Mira variables. It is an asymptotic giant branch star.
570 Gm (3.8 au) – length of the tail of Comet Hyakutake measured by Ulysses; the actual value could be much higher
590 Gm (3.9 au) – diameter of the Pistol Star, a blue hypergiant star
591 Gm (4.0 au) – minimum distance between the Earth and Jupiter
780 Gm (5.2 au) – average distance between Jupiter and the Sun
785 Gm (5.25 au) – diameter of Rho Cassiopeiae, a rare yellow hypergiant star
947 Gm (6.4 au) – diameter of Antares A
1 terametre
The terametre (SI symbol: Tm) is a unit of length in the metric system equal to 1000000000000 metres (1012 m).
To help compare different distances, this section lists lengths starting at 1012 m (1 Tm or 1 billion km or 6.7 astronomical units).
≈1 Tm – 6.7 au – diameter of the red supergiant Betelgeuse based on multiple angular diameter estimates
1.032 Tm – 6.9 au – diameter of the blue hypergiant Eta Carinae (at optical depth 2/3)
1.079 Tm – 7.2 au – one light-hour
1.4 Tm – 9.5 au – average distance between Saturn and the Sun
1.47 Tm – 9.9 au – diameter of HR 5171 A, a yellow hypergiant star
1.5 Tm – 10 au – estimated diameter of VV Cephei A, a red hypergiant with a blue dwarf companion.
1.75 Tm – 11.7 au – estimated diameter of Mu Cephei, a red supergiant (possibly hypergiant) among the largest-known stars.
2 Tm – 13.2 au – estimated diameter of VY Canis Majoris, a red hypergiant that is among the largest-known stars
2.1 Tm – 14.2 au – estimated diameter of RSGC1-FO1, the largest star in the Galaxy.
2.143 Tm – 14.3 au – estimated diameter of WOH G64, possibly the largest star known in the Large Magellanic Cloud.
2.9 Tm – 19.4 au – average distance between Uranus and the Sun
10 terametres
To help compare different distances this section lists lengths starting at 1013 m (10 Tm or 10 billion km or 67 astronomical units).
10 Tm – 67 AU – diameter of a hypothetical quasi-star
11.1 Tm – 74.2 AU – distance that Voyager 1 began detecting returning particles from termination shock
11.4 Tm – 76.2 AU – perihelion distance of 90377 Sedna
12.1 Tm – 70 to 90 AU – distance to termination shock (Voyager 1 crossed at 94 AU)
12.9 Tm – 86.3 AU – distance to 90377 Sedna in March 2014
13.2 Tm – 88.6 AU – distance to Pioneer 11 in March 2014
14.1 Tm – 94.3 AU – estimated radius of the Solar System
14.4 Tm – 96.4 AU – distance to Eris in March 2014 (now near its aphelion)
15.1 Tm – 101 AU – distance to heliosheath
16.5 Tm – 111 AU – distance to Pioneer 10 as of March 2014
16.6 Tm – 111.2 AU – distance to Voyager 2 as of May 2016
18 Tm – 123.5 AU – distance between the Sun to the farthest dwarf planet in the Solar System, the Farout 2018 VG18
19.5 Tm – 132.7 AU – distance between the Sun to one of the farthest known objects in the solar system, 2018 AG37 (FarFarOut)
100 terametres
To help compare different distances this section lists lengths starting at 1014 m (100 Tm or 100 billion km or 670 astronomical units).
140 Tm – 937 AU – aphelion distance of 90377 Sedna
142.1 Tm – 950 AU – average distance of the hypothetical Planet 9.
172 Tm – 1150 AU – Schwarzschild diameter of H1821+643, one of the most massive black holes known
181 Tm – 1210 AU – one light-week
240.4 Tm – 1607 AU – approximate Schwarzschild diameter of TON-618, previously the most massive black hole.
308.568 Tm – 2063 AU – 1 centiparsec
577.2 Tm – 3859 AU – Schwarzschild diameter of the ultramassive Black Hole in the center of the Supergiant Elliptical Galaxy IC1101.
590.8 Tm – 3949 AU – Schwarzschild diameter of Phoenix A, the most massive black hole.
757 Tm – 5059 AU – radius of the Stingray Nebula
777 Tm – 5180 AU – one light-month
1 petametre
The petametre (SI symbol: Pm) is a unit of length in the metric system equal to 1015 metres.
To help compare different distances this section lists lengths starting at 1015 m (1 Pm or 1 trillion km or 6685 astronomical units (AU) or 0.11 light-years).
1.0 Pm = 0.105702341 light-years
1.9 Pm ± 0.5 Pm = 12,000 AU = 0.2 light-year radius of Cat's Eye Nebula's inner core
3.08568 Pm = 20,626 AU = 1 deciparsec
4.7 Pm = 30,000 AU = half-light-year diameter of Bok globule Barnard 68
7.5 Pm – 50,000 AU – possible outer boundary of Oort cloud (other estimates are 75,000 to 125,000 or even 189,000 AU (1.18, 2, and 3 light-years, respectively))
9.5 Pm – 63,241.1 AU – one light-year, the distance light travels in one year
9.9 Pm – 66,000 AU – aphelion distance of the C/1999 F1 (Catalina)
10 petametres
To help compare different distances this section lists lengths starting at 1016 m (10 Pm or 66,800 AU, 1.06 light-years).
15 Pm – 1.59 light-years – possible outer radius of Oort cloud
20 Pm – 2.11 light-years – maximum extent of influence of the Sun's gravitational field
30.9 Pm – 3.26 light-years – 1 parsec
39.9 Pm – 4.22 light-years – distance to Proxima Centauri (nearest star to Sun)
81.3 Pm – 8.59 light-years – distance to Sirius
94.6 Pm – 1 light-decade
100 petametres
To help compare different distances this section lists lengths between 1017 m (100 Pm or 11 light-years) and 1018 m (106 light-years).
110 Pm – 12 light-years – Distance to Tau Ceti
230 Pm – 24 light-years – diameter of the Orion Nebula
240 Pm – 25 light-years – Distance to Vega
260 Pm – 27 light-years – Distance to Chara, a star approximately as bright as the Sun. Its faintness gives an idea how the Sun would appear when viewed from this distance.
308.568 Tm – 32.6 light-years – 1 dekaparsec
350 Pm – 37 light-years – distance to Arcturus
373.1 Pm – 39.44 light-years – distance to TRAPPIST-1, a star recently discovered to have 7 planets around it
400 Pm – 42 light-years – distance to Capella
620 Pm – 65 light-years – distance to Aldebaran
750 Pm – 79.36 light-years – distance to Regulus
900 Pm – 92.73 light-years – distance to Algol
946 Pm – 1 light-century
1 exametre
The exametre (SI symbol: Em) is a unit of length in the metric system equal to 1018 metres. To help compare different distances this section lists lengths between 1018 m (1 Em or 105.7 light-years) and 1019 m (10 Em or 1,057 light-years).
1.2 Em – 129 light-years – diameter of Messier 13 (a typical globular cluster)
1.6 Em – 172 ± 12.5 light-years – diameter of Omega Centauri (one of the largest-known globular clusters, perhaps containing over a million stars)
3.08568 Em – 326.1 light-years – 1 hectoparsec
3.1 Em – 310 light-years – distance to Canopus according to Hipparcos
3.9 Em – 410 light-years – distance to Betelgeuse according to Hipparcos
6.2 Em – 650 light-years – distance to the Helix Nebula, located in the constellation Aquarius
8.2 Em – 860 light-years – distance to Rigel according to Hipparcos
9.4 Em — 1 light-millennium – 1000 light-years
10 exametres
To help compare different orders of magnitude, this section lists distances starting at 10 Em (1019 m or 1,100 light-years).
10.6 Em – 1,120 light-years – distance to WASP-96b
13 Em – 1,300 light-years – distance to the Orion Nebula
14 Em – 1,500 light-years – approximate thickness of the plane of the Milky Way galaxy at the Sun's location
14.2 Em – 1,520 light-years – diameter of the NGC 604
30.8568 Em – 3,261.6 light-years – 1 kiloparsec
31 Em – 3,200 light-years – distance to Deneb according to Hipparcos
46 Em – 4,900 light-years – distance to OGLE-TR-56, the first extrasolar planet discovered using the transit method
47 Em – 5,000 light-years – distance to the Boomerang Nebula, coldest place known (1 K)
53 Em – 5,600 light-years – distance to the globular cluster M4 and the extrasolar planet PSR B1620-26 b within it
61 Em – 6,500 light-years – distance to Perseus Spiral Arm (next spiral arm out in the Milky Way galaxy)
71 Em – 7,500 light-years – distance to Eta Carinae
94.6073 Em – 1 light-decamillennium = 10,000 light-years
100 exametres
To help compare different orders of magnitude, this section lists distances starting at 100 Em (1020 m or 11,000 light-years).
150 Em – 16,000 light-years – diameter of the Small Magellanic Cloud, a dwarf galaxy orbiting the Milky Way
200 Em – 21,500 light-years – distance to OGLE-2005-BLG-390Lb
240 Em – 25,000 light-years – distance to the Canis Major Dwarf Galaxy
260 Em – 28,000 light-years – distance to the center of the Galaxy
400 Em – 48,000 light years – diameter of the Fireworks Galaxy
830 Em – 88,000 light-years – distance to the Sagittarius Dwarf Elliptical Galaxy
946 Em – 1 light-centum-millennium = 100,000 light-years
1 zettametre
The zettametre (SI symbol: Zm) is a unit of length in the metric system equal to 1021 metres.
To help compare different orders of magnitude, this section lists distances starting at 1 Zm (1021 m or 110,000 light-years).
1.7 Zm – 179,000 light-years – distance to the Large Magellanic Cloud, largest satellite galaxy of the Milky Way
<1.9 Zm – <200,000 light-years – revised estimated diameter of the disc of the Milky Way Galaxy. The size was previously thought to be half of this.
2.0 Zm – 210,000 light-years – distance to the Small Magellanic Cloud.
2.3 Zm – 240,000 light-years – diameter of the Andromeda Galaxy, the nearest major Galaxy.
2.8 Zm – 300,000 light-years – distance to the Intergalactic Wanderer, one of the most distant globular clusters of the Milky Way
8.5 Zm – 900,000 light-years – distance to the Leo I Dwarf Galaxy, farthest-known Milky Way satellite galaxy
9.5 Zm – 1 light-megaannum = 1,000,000 light-years
10 zettametres
To help compare different orders of magnitude, this section lists distances starting at 10 Zm (1022 m or 1.1 million light-years).
16.7 Zm – 1.76 million light-years – diameter of the Galaxy ESO 383-76, one of the largest galaxies known.
24 Zm – 2.5 million light-years – distance to the Andromeda Galaxy, the nearest major galaxy.
27 Zm – 2.9 million light-years – distance to the Triangulum Galaxy.
30.8568 Zm – 3.2616 million light-years – 1 megaparsec
40 Zm – 4.2 million light-years – distance to the IC 10, a distant member of the Local Group of galaxies
49.2 Zm – 5.2 million light-years – width of the Local Group of galaxies
56.7 Zm – 6 million light-years – old estimate of the diameter of IC1101, a Supergiant galaxy located in Abell 2029.
95 Zm – 10 million light-years – distance to the Sculptor Galaxy in the Sculptor Group of galaxies
95 Zm – 10 million light-years – distance to the Maffei 1, the nearest giant elliptical galaxy in the Maffei 1 Group
100 zettametres
To help compare different orders of magnitude, this section lists distances starting at 100 Zm (1023 m or 11 million light-years).
140 Zm – 15 million light-years – distance to Centaurus A galaxy
150 Zm – 16 million light-years – length of the entire structure of the Alcyoneus Galaxy.
250 Zm – 27 million light-years – distance to the Pinwheel Galaxy
280 Zm – 30 million light-years – distance to the Sombrero Galaxy
570 Zm – 60 million light-years – approximate distance to the Virgo Cluster, nearest galaxy cluster
620 Zm – 65 million light-years – approximate distance to the Fornax Cluster
800 Zm – 85 million light-years – approximate distance to the Eridanus Cluster
1 yottametre
The yottametre (SI symbol: Ym) is a unit of length in the metric system equal to 1024 metres.
To help compare different orders of magnitude, this section lists distances starting at 1 Ym (1024 m or 105.702 million light-years).
1.2 Ym – 127 million light-years – distance to the closest observed gamma ray burst GRB 980425
1.3 Ym – 137 million light-years – distance to the Centaurus Cluster of galaxies, the nearest large supercluster
1.9 Ym – 200 million light-years – distance to the great attractor.
1.9 Ym – 201 million light-years – diameter of the Local Supercluster
2.17 Ym – 1 light-galactic-years – 230 million light-years
2.3 Ym – 225 to 250 million light-years – distance light travels in vacuum in one galactic year
2.8 Ym – 296 million light-years – distance to the Coma Cluster
3.15 Ym – 330 million light years – diameter of the Boötes Void
3.2 Ym – 338 million light-years – distance to Stephan's Quintet
4.7 Ym – 496 million light-years – length of the CfA2 Great Wall, one of the largest observed superstructures in the Universe
4.7 Ym – 500 million light-years – approximate diameter of the Laniakea supercluster, the supercluster complex that houses the Milky Way.
10 yottametres
To help compare different orders of magnitude, this section lists distances starting at 10 Ym (1025 m or 1.1 billion light-years). At this scale, expansion of the universe becomes significant. Distance of these objects are derived from their measured redshifts, which depends on the cosmological models used.
13 Ym – 1.37 billion light-years – length of the South Pole Wall
13 Ym – 1.38 billion light-years – length of the Sloan Great Wall
18 Ym – redshift 0.16 – 1.9 billion light-years – distance to the quasar 3C 273 (light travel distance)
30.8568 Ym – 3.2616 billion light-years – 1 gigaparsec
31.2204106 Ym − 3.3 billion light-years − length of the Giant Arc, a large cosmic structure discovered in 2021
33 Ym – 3.5 billion light-years – maximum distance of the 2dF Galaxy Redshift Survey (light travel distance)
37.8 Ym – 4 billion light-years – length of the Huge-LQG
75 Ym – redshift 0.95 – 8 billion light-years – approximate distance to the supernova SN 2002dd in the Hubble Deep Field North (light travel distance)
85 Ym – redshift 1.6 – 9 billion light-years – approximate distance to the gamma-ray burst GRB 990123 (light travel distance)
94.6 Ym – 10 billion light-years – approximate distance to quasar OQ172
94.6 Ym – 10 billion light-years – length of the Hercules–Corona Borealis Great Wall, one of the largest and most massive-known cosmic structures known
100 yottametres
To help compare different orders of magnitude, this section lists distances starting at 100 Ym (1026 m or 11 billion light-years). At this scale, expansion of the universe becomes significant. Distance of these objects are derived from their measured redshifts, which depend on the cosmological models used.
124 Ym – redshift 7.54 – 13.1 billion light-years – light travel distance (LTD) to the quasar ULAS J1342+0928, the most distant-known quasar as of 2017
130 Ym – redshift 1,000 – 13.8 billion light-years – distance (LTD) to the source of the cosmic microwave background radiation; radius of the observable universe measured as a LTD
260 Ym – 27.4 billion light-years – diameter of the observable universe (double LTD)
440 Ym – 46 billion light-years – radius of the universe measured as a comoving distance
590 Ym – 62 billion light-years – cosmological event horizon: the largest comoving distance from which light will ever reach us (the observer) at any time in the future
886.48 Ym – 93.7 billion light-years – the diameter of the observable universe (twice the particle horizon); however, there might be unobserved distances that are even greater.
1 ronnametre
The ronnametre (SI symbol: Rm) is a unit of length in the metric system equal to 1027 metres.
To help compare different orders of magnitude, this section lists distances starting at 1 Rm (1027 m or 105.7 billion light-years). At this scale, expansion of the universe becomes significant. Distance of these objects are derived from their measured redshifts, which depend on the cosmological models used.
>1 Rm – >105.7 billion light-years – size of universe beyond the cosmic light horizon, depending on its curvature; if the curvature is zero (i.e. the universe is spatially flat), the value can be infinite (see Shape of the universe) as previously mentioned.
2.764 Rm - 292.2 billion light-years – circumference of the observable universe, as it is in the shape of a sphere.
221.617 Rm - 23.425 trillion light-years - circumference of the observable universe, as it is in the shape of a hypersphere.
1 quettametre
The quettametre (SI symbol: Qm) is a unit of length in the metric system equal to 1030 metres.
Upper limits
≈101010122light-years – the possible size of the universe after cosmological inflation.
≈∞ light-years — theoretical size of the multiverse if it exists.