Millimetres to Kilometres Converter
Convert millimetres (mm) to kilometres (km) instantly. Length conversions come up when reading overseas furniture specs, cycling the Round Island Route in kilometres while a foreign app shows miles, or checking marine distances in the Singapore Strait in nautical miles.
Result
- Kilometres
- 1.000000e-6 km
How to use the millimetres to kilometres converter
- Enter the millimetres (mm).
- The results update as you type, or press Calculate.
- Read the kilometres first, then the supporting figures below it.
Formula
Kilometres = millimetres × 1.000000e-06
Worked example
For example, with these inputs:
- Millimetres (mm): 1
the calculator returns:
- Kilometres: 1.000000e-6 km
Millimetres to Kilometres table
| Millimetres | Kilometres |
|---|---|
| 1 mm | 1.000000e-6 km |
| 2 mm | 2.000000e-6 km |
| 5 mm | 5.000000e-6 km |
| 10 mm | 1.000000e-5 km |
| 20 mm | 2.000000e-5 km |
| 25 mm | 2.500000e-5 km |
| 50 mm | 5.000000e-5 km |
| 100 mm | 1.000000e-4 km |
| 250 mm | 0.00025 km |
| 500 mm | 0.0005 km |
| 1,000 mm | 0.001 km |
About this conversion
Length conversions come up when reading overseas furniture specs, cycling the Round Island Route in kilometres while a foreign app shows miles, or checking marine distances in the Singapore Strait in nautical miles.
For everyday use, three or four significant figures are usually enough. Engineering, science and trade documents may need more, and rounding should happen only at the end of a calculation.
Writing the units next to every number while you work is the simplest way to avoid mistakes. If the units do not cancel to leave the one you want, the calculation is set up wrongly.
Frequently asked questions
How many kilometres are in one millimetre?
1 mm = 1.000000e-6 km.
How do I convert mm to km?
Kilometres = millimetres × 1.000000e-06.