Convert Millimeters to Kilometers
mm to km · length conversion
What are millimeters and kilometers?
A millimeter is one-thousandth of a meter, about the thickness of a credit card. A kilometer is 1,000 meters, the standard metric unit for road distances. For scale: a doorway is about 2 m (6.6 ft) tall, and a marathon is 42.2 km (26.2 mi).
How to convert millimeters to kilometers
1 mm = 0.000001 km. To convert, multiply the number of millimeters by 0.000001. For example, 5 mm = 0.000005 km, and 20 mm = 0.00002 km. To go the other way, multiply kilometers by 1,000,000 (since 1 km = 1,000,000 mm).
Millimeters to Kilometers conversion table
| Millimeters (mm) | Kilometers (km) |
|---|---|
| 1 | 0.000001 |
| 2 | 0.000002 |
| 5 | 0.000005 |
| 10 | 0.00001 |
| 20 | 0.00002 |
| 50 | 0.00005 |
| 100 | 0.0001 |
FAQ
What is 1 mm in km?
1 mm = 0.000001 km. To convert any amount, multiply the number of millimeters by 0.000001.
How do I convert kilometers back to millimeters?
Go the other way: 1 km = 1,000,000 mm, so multiply kilometers by 1,000,000 to get millimeters.
Is a millimeter bigger than a kilometer?
No — 1 mm is the smaller unit, equal to 0.000001 km (it takes 1,000,000 mm to make one km).
Are these length conversions exact?
They use the standard internationally-defined conversion factors. Results are rounded to six significant figures for readability, which is accurate enough for everyday and most technical use.