Orders of magnitude (length)


The following are examples of orders of magnitude for different lengths.

Overview

Detailed list

To help compare different orders of magnitude, the following list describes various lengths between metres and 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 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.

Subatomic scale

Atomic to cellular scale

Factor MultipleValueItem
10−151 femtometre 1 fmApproximate limit of the gluon-mediated color force between quarks
10−151 femtometre 1.5 fmEffective cross section radius of an 11 MeV proton
10−151 femtometre 2.81794 fmClassical electron radius
10−151 femtometre 3 fmApproximate limit of the meson-mediated nuclear binding force
10−151 femtometre 750 to 822.25 fmLongest wavelength of gamma rays
10−121 picometre 1.75 to 15 fmdiameter range of the atomic nucleus
10−121 picometre 1 pmDistance between atomic nuclei in a white dwarf
10−121 picometre 2.4 pmCompton wavelength of electron
10−121 picometre 5 pmWavelength of shortest X-rays
10−1110 pm28 pmRadius of helium atom
10−1110 pm53 pmBohr radius
10−10100 pm100 pm1 ångström
10−10100 pm154 pmLength of a typical covalent bond
10−10100 pm280 pmAverage size of the water molecule
10−10100 pm500 pmWidth of protein α helix
10−91 nanometre 1 nmdiameter of a carbon nanotube diameter of smallest transistor gate
10−91 nanometre 2 nmdiameter of the DNA helix
10−91 nanometre 2.5 nmSmallest microprocessor transistor gate oxide thickness
10−91 nanometre 3.4 nmLength of a DNA turn
10−91 nanometre 6–10 nmThickness of cell membrane
10−810 nm10 nmUpper range of thickness of cell wall in Gram-negative bacteria
10−810 nm10 nm, the 10 nanometre was the smallest semiconductor device fabrication node
10−810 nm40 nmExtreme ultraviolet wavelength
10−810 nm50 nmFlying height of the head of a hard disk
10−7100 nm121.6 nmWavelength of the Lyman-alpha line
10−7100 nm120 nmTypical diameter of the human immunodeficiency virus
10−7100 nm400–700 nmApproximate wavelength range of visible light

Cellular to human scale

Factor MultipleValueItem
10−61 micrometre
1–4 μmTypical length of a bacterium
10−61 micrometre
4 μmTypical diameter of spider silk
10−61 micrometre
7 μmTypical size of a red blood cell
10−510 μm10 μmTypical size of a fog, mist, or cloud water droplet
10−510 μm10 μmWidth of transistors in the Intel 4004, the world's first commercial microprocessor
10−510 μm12 μmWidth of acrylic fiber
10−510 μm17–181 μmWidth range of human hair
10−4100 μm340 μmSize of a pixel on a 17-inch monitor with a resolution of 1024×768
10−4100 μm560 μmThickness of the central area of a human cornea or, diameter of a grain of salt.
10−4100 μm750 μmMaximum diameter of Thiomargarita namibiensis, the second largest bacterium ever discovered
10−31 millimetre ~5 mmLength of an average flea is 1–10 mm
10−31 millimetre 2.54 mmOne-tenth inch; distance between pins in DIP electronic components
10−31 millimetre 5.70 mmApproximate diameter of the projectile in 5.56×45mm NATO ammunition
10−21 centimetre 20 mmApproximate width of an adult human finger
10−21 centimetre 54 mm × 86 mmDimensions of a credit card, according to the ISO/IEC 7810 ID-1 standard
10−21 centimetre 73–75 mmdiameter of a baseball, according to Major League Baseball guidelines
10−11 decimetre 120 mmdiameter of a compact disc
10−11 decimetre 660 mmLength of the longest pine cones, produced by the sugar pine
10−11 decimetre 900 mmAverage length of a rapier, a fencing sword

Human to astronomical scale

Factor MultipleValueItem
1 1 metre 1 m Since 2019, defined as the length of the path travelled by light in a vacuum during a time interval of 1/299,792,458 of a second, where the second is defined by a hyperfine transition frequency of caesium.
1 1 metre 2.72 mHeight of Robert Wadlow, tallest-known human.
1 1 metre 8.38 mLength of a London bus
1011 decametre 33 mLength of the longest-known blue whale
1011 decametre 52 mHeight of the Niagara Falls
1011 decametre 93.47 mHeight of the Statue of Liberty
1021 hectometre 105 mLength of a typical football field
1021 hectometre 137 m Height of the Great Pyramid of Giza
1021 hectometre 300 mHeight of the Eiffel Tower, one of the famous monuments of Paris
1021 hectometre 979 mHeight of the Salto Angel, the world's highest free-falling waterfall
1031 kilometre 2.3 kmLength of the Three Gorges Dam, the largest dam in the world
1031 kilometre 3.1 kmNarrowest width of the Strait of Messina, separating Italy and Sicily
1031 kilometre 8.848 kmHeight of Mount Everest, the highest mountain on Earth
10410 km10.9 kmDepth of the Challenger Deep in the Mariana Trench, the deepest-known point on Earth's surface
10410 km27 kmCircumference of the Large Hadron Collider, the largest and highest energy particle accelerator
10410 km42.195 kmLength of a marathon
105100 km100 kmThe distance the IAU considers to be the limit to space, called the Karman line
105100 km163 kmLength of the Suez Canal, connecting the Mediterranean Sea to the Red Sea
105100 km491 kmLength of the Pyrenees, the mountain range separating Spain and France
105100 km600 kmThermosphere height
105100 km974.6 kmGreatest diameter of the dwarf planet Ceres.
1061 megametre 2.38 Mmdiameter of dwarf planet Pluto, formerly the smallest planet category in the Solar System
1061 megametre 3.48 Mmdiameter of the Moon
1061 megametre 5.2 MmTypical distance covered by the winner of the 24 Hours of Le Mans automobile endurance race
1061 megametre 6.259 MmLength of the Great Wall of China
1061 megametre 6.371 MmAverage radius of Earth
1061 megametre 6.378 MmEquatorial radius of Earth
1061 megametre 6.6 MmApproximate length of the two longest rivers, the Nile and the Amazon
1061 megametre 7.821 MmLength of the Trans-Canada Highway
1061 megametre 9.288 MmLength of the Trans-Siberian Railway, longest in the world