How to convert millimeters to kilometers
km = mm × 0.000001Multiply the value in millimeters by 0.000001. To go the other way, multiply by 1,000,000 (or divide by 0.000001).
A millimeter is smaller than a kilometer: it takes 1,000,000 millimeters to make one kilometer.
Worked examples
- 1 millimeter1 mm × 0.000001 = 0.000001 km
- 5 millimeters5 mm × 0.000001 = 0.000005 km
- 10 millimeters10 mm × 0.000001 = 0.00001 km
- 20 millimeters20 mm × 0.000001 = 0.00002 km
- 100 millimeters100 mm × 0.000001 = 0.0001 km
Millimeters to kilometers conversion table
Values are calculated by the conversion engine and rounded to 8 significant figures.
| Millimeters (mm) | Kilometers (km) |
|---|---|
| 0.1 mm | 1×10⁻⁷ km |
| 0.25 mm | 2.5×10⁻⁷ km |
| 0.5 mm | 5×10⁻⁷ km |
| 1 mm | 0.000001 km |
| 2 mm | 0.000002 km |
| 3 mm | 0.000003 km |
| 4 mm | 0.000004 km |
| 5 mm | 0.000005 km |
| 6 mm | 0.000006 km |
| 7 mm | 0.000007 km |
| 8 mm | 0.000008 km |
| 9 mm | 0.000009 km |
| 10 mm | 0.00001 km |
| Millimeters (mm) | Kilometers (km) |
|---|---|
| 12 mm | 0.000012 km |
| 15 mm | 0.000015 km |
| 20 mm | 0.00002 km |
| 25 mm | 0.000025 km |
| 30 mm | 0.00003 km |
| 40 mm | 0.00004 km |
| 50 mm | 0.00005 km |
| 75 mm | 0.000075 km |
| 100 mm | 0.0001 km |
| 250 mm | 0.00025 km |
| 500 mm | 0.0005 km |
| 1,000 mm | 0.001 km |
About the units
Millimeter (mm)
One thousandth of a metre. Millimetres are the standard unit on engineering drawings, rulers and rainfall gauges; a credit card is about 0.76 mm thick. One millimeter equals 0.001 meters (m).
Kilometer (km)
One thousand metres. Kilometres measure road distances and running races in most countries; a 10K race is 10 km, about 6.2 miles. One kilometer equals 1,000 meters (m).
Frequently asked questions
How many kilometers are in one millimeter?
There are 0.000001 kilometers in one millimeter, and this value is exact by definition.
How do I convert millimeters to kilometers?
Multiply the number of millimeters by 0.000001. For example, 10 mm × 0.000001 = 0.00001 km.
How many millimeters are in one kilometer?
One kilometer equals 1,000,000 millimeters. That is the reverse factor, 1 ÷ 0.000001.
What is 10 millimeters in kilometers?
10 mm = 0.00001 km.
Is this mm to km converter accurate?
Yes. Both units are defined exactly in terms of SI units, so the conversion factor is exact; results are shown to 12 significant figures by default and you can change precision in the converter. Calculations run in your browser using the same tested engine that generated this page.