Thanks to Tim Talbert for providing some of the data.

Also see a similar page on Wikipedia.

1.616x10^{-35} m | 1.616x10^{-35} m | the Planck length (the smallest measurement of length that has meaning) |

1x10^{-15} m | 1x10^{-15} m | one fermi |

1 fm | 1x10^{-15} m | diameter of proton (in the nucleus) |

2.2 fm | 2.2x10^{-15} m | classical diameter of neutron |

3.8 fm | 3.8x10^{-15} m | diameter of the nucleus of a helium atom |

5.635882 fm | 5.635882x10^{-15} m | classical diameter of an electron |

7.2 fm | 7.2x10^{-15} m | diameter of the nucleus of an aluminum atom |

14 fm | 1.4x10^{-14} m | diameter of the nucleus of a gold atom |

(The classical electron diameter is bigger than the proton diameter because the proton's size was measured in the nucleus, where it is trapped in a very deep, narrow potential well. The electron is in a comparatively wide, shallow well, so it takes up much more space. Talking about the sizes of subatomic particles is fairly meaningless anyway; in one sense, electrons and protons are point particles, with no size. And in quantum mechanics, we can only talk about the probability of finding a particle at a particular point, and cannot specify (or define) the exact position and size of a particle. The "classical electron radius" tells us little about the actual physical size of the electron. In short, I'm oversimplifying things.)

14 fm | 1.4x10^{-14} m | diameter of the nucleus of a gold atom |

1,000 fm | 1x10^{-12} m | one picometer |

1 pm | 1x10^{-12} m | wavelength of gamma rays |

1 pm | 1x10^{-12} m | wavelength of gamma rays |

38 pm | 3.8x10^{-11} m | diameter of flourine ion |

52.9 pm | 5.29x10^{-11} m | most likely distance from electron to nucleus in a hydrogen atom (bohr radius) |

74.13 pm | 7.413x10^{-11} m | distance between bonded hydrogen atoms |

100 pm | 1x10^{-10} m | one angstrom |

120 pm | 1.2x10^{-10} m | Van Der Waals radius of hydrogen atoms (max distance between atoms that are not bonded) |

200 pm | 2x10^{-10} m | resolution (size of smallest visible object) of a transmission electron microscope |

248.2 pm | 2.482x10^{-10} m | distance between bonded iron atoms |

275 pm | 2.75x10^{-10} m | Van Der Waals radius of potassium atoms (max distance between atoms that are not bonded) |

282 pm | 3x10^{-10} m | diameter of water molecule |

340 pm | 3.4x10^{-10} m | distance between base pairs in a DNA molecule |

380 pm | 3.8x10^{-10} m | diameter of xenon ion |

530.9 pm | 5.309x10^{-10} m | distance between bonded cesium atoms |

530.9 pm | 5.309x10^{-10} m | distance between bonded cesium atoms |

1,000 pm | 1x10^{-9} m | one nanometer |

1 nm | 1x10^{-9} m | diameter of glucose molecule |

2 nm | 2x10^{-9} m | diameter of DNA helix |

5 nm | 5x10^{-9} m | diameter of insulin molecule |

6 nm | 6x10^{-9} m | diameter of a hemoglobin molecule |

10 nm | 1x10^{-8} m | thickness of cell wall (gram negative bacteria) |

75 nm | 7.5x10^{-8} m | size of typical virus |

90 nm | 9x10^{-8} m | length of transistor gate in a Pentium 4 chip (minimum feature size) |

125 nm | 1.25x10^{-7} m | thickness of gold leaf |

130 nm | 1.3x10^{-7} m | length of transistor gate in a Pentium 3 chip (1.4 Ghz) |

200 nm | 2x10^{-7} m | diameter of smallest bacteria |

200 nm | 2x10^{-7} m | resolution (size of smallest visible object) of an optical microscope |

260 nm | 2.6x10^{-7} m | length of the smallest transistor in a Pentium 3 chip |

410 nm | 4.1x10^{-7} m | wavelength of violet light |

680 nm | 6.8x10^{-7} m | wavelength of red light |

1,000 nm | 1x10^{-6} m | one micrometer (micron) |

1 µm | 1x10^{-6} m | size of typical bacterium |

1 µm | 1x10^{-6} m | diameter of sperm cell |

1.5 µm | 1.5x10^{-6} m | length of transistor gate in an Intel 286 chip |

1.7 µm | 1.7x10^{-6} m | diameter of average human cell nucleus |

2.4 µm | 2.4x10^{-6} m | thickness of red blood cell |

3 µm | 3x10^{-6} m | length of transistor gate in an Intel 8086 chip |

4 µm | 4x10^{-6} m | diameter of capillary |

7 µm | 7x10^{-6} m | diameter of a single yeast organism |

8.4 µm | 8.4x10^{-6} m | diameter of red blood cell |

10 µm | 1x10^{-5} m | diameter of average cell in human body |

10 µm | 1x10^{-5} m | size of a grain of talcum powder |

16 µm | 1.6x10^{-5} m | length of the smallest transistor in the first 6502 chips |

16 µm | 1.6x10^{-5} m | length of the smallest transistor in the first 6502 chips |

20 µm | 2x10^{-5} m | length of the smallest transistor in an Intel 4004 (the first microprocessor) |

20 µm | 2.0x10^{-5} m | diameter of a small grain of sand |

25 µm | 2.5x10^{-5} m | length of sperm cell |

25 µm | 2.5x10^{-5} m | diameter of a human hair |

83.82 µm | 8.382x10^{-5} m | typical thickness of a piece of paper |

100 µm | 1x10^{-4} m | mimimum size of object the human eye can resolve unaided |

100 µm | 1x10^{-4} m | diameter of human fertilized egg cell |

100 µm | 1x10^{-4} m | size of a grain of salt |

110 µm | 1.1x10^{-4} m | thickness of a dollar bill |

300 µm | 3x10^{-4} m | diameter of a period on a typewriter |

375 µm | 3.7x10^{-4} m | diameter of the most common type of optical fiber |

750 µm | 7.5x10^{-4} m | size of largest known bacterium |

1,000 µm | 1x10^{-3} m | one millimeter |

1.7 mm | 1.7x10^{-3} m | diameter of the head of the average pin |

2 mm | 2x10^{-3} m | diameter of a large grain of sand |

2 mm | 2x10^{-3} m | diameter of a large grain of sand |

2 mm | 2x10^{-3} m | size of a small ant |

4.234 mm | 4.234x10^{-3} m | height of a line of text in 12-point type |

10 mm | 1x10^{-2} m | one centimeter |

1.7 cm | 1.7x10^{-2} m | wavelength of 20khz note (highest that can be heard) at 27 degrees celsius |

2.5 cm | 2.5x10^{-2} m | size of a large ant |

2.54 cm | 2.540x10^{-2} m | one inch |

8.5 cm | 8.5x10^{-2} m | length of largest human chromosome if it were stretched end-to-end |

12.2 cm | 1.22x10^{-1} m | wavelength of microwaves in a microwave oven |

30 cm | 3.0x10^{-1} m | one foot |

79 cm | 7.9x10^{-1} m | wavelength of 440 hertz note (A above middle C) at 27 degrees celsius |

91 cm | 9.1x10^{-1} m | one yard |

1 m | 1 m | one meter |

1 m | 1 m | one meter |

3 m | 3 m | average wavelength of FM radio waves |

17 m | 1.7x10^{1} m | wavelength of 20 hertz note (lowest that can be heard) at 27 degrees celsius |

299.7925 m | 2.997925x10^{2} m | distance light travels in one microsecond, in a vacuum |

343 m | 3.43x10^{2} m | distance sound travels in one second (at 20 degress celsius) |

415 m | 4.1x10^{2} m | distance a bullet travels per second, when fired from a .22 |

299.7925 km | 2.997925x10^{5} m | distance light travels in one millisecond, in a vacuum |

300 km | 3x10^{5} m | height of space shuttle's typical orbit |

354 km | 3.54x10^{5} m | average altitude of International Space Station |

640 km | 6.4x10^{5} m | height of lowest point of inner Van Allen belt |

792 km | 7.92x10^{5} m | altitude of Iridium satellites (LEO) |

825 km | 8.25x10^{5} m | altitude of Orbcomm satellites (LEO) |

914 km | 9.14x10^{5} m | diameter of the asteroid Ceres |

1,000 km | 1x10^{6} m | thickness of earth's atmosphere |

1,375 km | 1.375x10^{6} m | height of Teledesic (low-earth orbit) satellites |

1,414 km | 1.414x10^{6} m | altitude of Globalstar satellites (LEO) |

2,274 km | 2.274x10^{6} m | diameter of Pluto at its equator |

2,890 km | 2.89x10^{6} m | depth of earth's outer (liquid) core |

3,474.8 km | 3.4748x10^{6} m | diameter of moon |

3,962 km | 3.962x10^{6} m | distance from New York to Los Angeles |

4,879.4 km | 4.8794x10^{6} m | diameter of Mercury at its equator |

5,150 km | 5.150x10^{6} m | diameter of Titan |

5,150 km | 5.150x10^{6} m | diameter of Titan |

5,150 km | 5.15x10^{6} m | depth of earth's inner (solid) core |

5,200 km | 5.2x10^{6} m | height of highest point of outer Van Allen belt |

5,262 km | 5.262x10^{6} m | diameter of Ganymede |

5,613 km | 5.613x10^{6} m | distance from New York to London |

6,378.14 km | 6.37814x10^{6} m | distance to center of Earth |

6,794.4 km | 6.7944x10^{6} m | diameter of Mars at its equator |

9,084 km | 9.084x10^{6} m | distance from London to Los Angeles |

9,380 km | 9.38x10^{6} m | mean distance from Phobos to Mars |

10,390 km | 1.039x10^{7} m | altitude of ICO satellites (MEO) |

12,103 km | 1.2103x10^{7} m | diameter of Venus at its equator |

12,756.2 km | 1.27562x10^{7} m | diameter of Earth at its equator |

20,200 km | 2.02x10^{7} m | altitude of GPS satellites |

23,460 km | 2.346x10^{7} m | mean distance from Deimos to Mars |

35,800 km | 3.58x10^{7} m | height of satellite in geostationary orbit |

47,810 km | 4.781x10^{7} m | min initial altitude of Geotail satellite (VHO) |

47,810 km | 4.781x10^{7} m | min initial altitude of Geotail satellite (VHO) |

49,492 km | 4.9492x10^{7} m | diameter of Neptune at its equator |

51,118 km | 5.1118x10^{7} m | diameter of Uranus at its equator |

120,536 km | 1.2053x10^{8} m | diameter of Saturn at its equator |

142,984 km | 1.4298x10^{8} m | diameter of Jupiter at its equator |

299,792.5 km | 2.997925x10^{8} m | distance light travels in one second, in a vacuum |

384,400 km | 3.844x10^{8} m | mean distance from earth to moon |

868,912 km | 8.68912x10^{8} m | max initial altitude of Geotail satellite (VHO) |

1,070,000 km | 1.07x10^{9} m | mean distance from Jupiter to Ganymede |

1,221,850 km | 1.22185x10^{9} m | mean distance from Saturn to Titan |

1,390,000 km | 1.39x10^{9} m | diameter of sun at its equator |

1,500,000 km | 1.5x10^{9} m | distance to SOHO satellite (L1 Lagrange point) |

1,500,000 km | 1.5x10^{9} m | distance to SOHO satellite (L1 Lagrange point) |

17,987,550 km | 1.798755x10^{10} m | distance light travels in one minute, in a vacuum |

57,910,000 km | 5.791x10^{10} m | mean distance of Mercury from the sun |

108,200,000 km | 1.082x10^{11} m | mean distance of Venus from the sun |

1 AU | 1.4959787x10^{11} m | mean distance of Earth from the sun (one astronomical unit) |

1.5236 AU | 2.2794x10^{11} m | mean distance of Mars from the sun |

2.766 AU | 4.139x10^{11} m | mean distance of the asteroid Ceres from the sun |

5.2028 AU | 7.7833x10^{11} m | mean distance of Jupiter from the sun |

7.2143607 AU | 1.079253x10^{12} m | distance light travels in one hour, in a vacuum |

1,212.0125 AU | 1.813145x10^{14} m | distance light travels in one week, in a vacuum |

25,000 AU | 3.7x10^{15} m | possible distance of Sol B from Sun |

63,239.737 AU | 9.460530x10^{15} m | distance light travels in one year (one light-year) |

1.5 ly | 1.4x10^{16} m | possible edge of Oort cloud |

3.26 ly | 3.08x10^{16} m | one parsec |

4.22 ly | 3.99x10^{16} m | distance to the star Proxima Centauri (nearest star other than sun) |

4.3 ly | 4.1x10^{16} m | distance to the stars Alpha Centauri A and B |

8.6 ly | 8.1x10^{16} m | distance to the star Sirius |

8.6 ly | 8.1x10^{16} m | distance to the star Sirius |

25.2 ly | 2.39x10^{17} m | distance to the star Vega |

33 ly | 3.2x10^{17} m | distance to the star Pollux |

36 ly | 3.5x10^{17} m | distance to the star Arcturus |

51 ly | 4.9x10^{17} m | distance to the star Castor |

77 ly | 7.3x10^{17} m | distance to the star Regulus |

300 ly | 2x10^{18} m | thickness of Milky Way Galaxy |

430 ly | 4.0x10^{18} m | distance to the star Polaris |

1.6 kly | 1.5x10^{19} m | distance to Horsehead Nebula |

1.6 kly | 1.5x10^{19} m | distance to Horsehead Nebula |

20 kly | 1x10^{20} m | diameter of Large Magellanic Cloud galaxy |

27 kly | 2.6x10^{20} m | distance to center of Milky Way Galaxy |

44 kly | 4.2x10^{20} m | diameter of M33 galaxy |

162 kly | 1.54x10^{21} m | diameter of Milky Way Galaxy |

200 kly | 1x10^{21} m | distance to Large Magellanic Cloud galaxy |

200 kly | 1x10^{21} m | diameter of M31 galaxy |

300 kly | 2x10^{21} m | distance to Small Magellanic Cloud galaxy |

300 kly | 2x10^{21} m | distance to Small Magellanic Cloud galaxy |

2,200 kly | 2.0x10^{22} m | distance to Andromeda galaxy |

3,000 kly | 2x10^{22} m | distance to Pisces galaxy |

4,000 kly | 3x10^{22} m | distance to IC 10 galaxy |

5,000 kly | 4x10^{22} m | distance to Pegasus galaxy |

11,000 kly | 1.0x10^{23} m | distance to the M81 galaxy cluster |

15,000 kly | 1.4x10^{23} m | distance to the M83 galaxy |

27,000 kly | 2.5x10^{23} m | distance to the M101 galaxy |

35,000 kly | 3.3x10^{23} m | distance to the M66 galaxy cluster |

37,000 kly | 3.5x10^{23} m | distance to the M51 galaxy cluster |

38,000 kly | 3.5x10^{23} m | distance to the M95 galaxy |

41,000 kly | 3.8x10^{23} m | distance to the M96 galaxy |

60,000 kly | 5x10^{23} m | distance to the Virgo galaxy cluster |

60,000 kly | 5x10^{23} m | distance to the Virgo galaxy cluster |

340,000 kly | 3.2x10^{24} m | distance to the Coma galaxy cluster |

2,000,000 kly | 1x10^{25} m | distance to brightest quasar (3C 273) |

4,000,000 kly | 3x10^{25} m | distance to quasar 3C 48 |

26,000,000 kly | 2.4x10^{26} m | distance to farthest known object (quasar SDSS_1044_0125) |