Convert kilometer to millimeter
1 km = 1,000,000 mm
sig figs
1 km = 1,000,000 mm
1 km in every length unit
| Planck length | 6.19e+37 lP |
| femtometer | 1.00e+18 fm |
| picometer | 1.00e+15 pm |
| bohr radius | 18,900,000,000,000 a0 |
| angstrom | 10,000,000,000,000 Å |
| nanometer | 1,000,000,000,000 nm |
| micrometer | 1,000,000,000 μm |
| thou | 39,400,000 thou |
| point | 2,830,000 pt |
| millimeter | 1,000,000 mm |
| pica | 236,000 pc |
| centimeter | 100,000 cm |
| inch | 39,400 in |
| decimeter | 10,000 dm |
| hand | 9,840 hh |
| link | 4,970 li |
| foot | 3,280 ft |
| US survey foot | 3,280 ftUS |
| yard | 1,090 yd |
| meter | 1,000 m |
| fathom | 547 ftm |
| rod | 199 rd |
| chain | 49.7 ch |
| cable length | 5.4 cb |
| furlong | 4.97 fur |
| kilometer | 1 km |
| mile | 0.621 mi |
| nautical mile | 0.54 nmi |
| league | 0.207 lea |
| megameter | 0.001 Mm |
| Earth radius | 0.000157 REarth |
| light-second | 0.00000334 ls |
| lunar distance | 0.0000026 LD |
| solar radius | 0.00000144 Rsun |
| light-minute | 5.56e-08 lmin |
| astronomical unit | 6.68e-09 AU |
| light-year | 1.06e-13 ly |
| parsec | 3.24e-14 pc |
| kiloparsec | 3.24e-17 kpc |
| megaparsec | 3.24e-20 Mpc |
| gigaparsec | 3.24e-23 Gpc |
How the conversion works
Multiply by 1,000,000 to go from kilometer to millimeter, or divide by it to go back. Every conversion on this site routes through the SI value (m) rather than a table of pairwise factors, so a round-trip returns exactly what you started with.
Going the other way? millimeter to kilometer: 1 mm = 0.000001 km.
kilometer to millimeter: common values
| 1 km | 1,000,000 mm |
| 2 km | 2,000,000 mm |
| 3 km | 3,000,000 mm |
| 5 km | 5,000,000 mm |
| 10 km | 10,000,000 mm |
| 15 km | 15,000,000 mm |
| 20 km | 20,000,000 mm |
| 25 km | 25,000,000 mm |
| 50 km | 50,000,000 mm |
| 75 km | 75,000,000 mm |
| 100 km | 100,000,000 mm |
| 250 km | 250,000,000 mm |
| 500 km | 500,000,000 mm |
| 1000 km | 1,000,000,000 mm |