millimeter to kilometer
Convert millimeter (mm) to kilometer (km). Use an editable length converter, conversion formula, and reference table.
1 mm = 0.000001 km
Conversion formula
One millimeter equals 0.000001 kilometer. Multiply your value in millimeter by this factor to get kilometer. For the reverse conversion, divide by the same factor.
Worked example
To convert 5 millimeter:5 × 0.000001 = 0.000005 km
Conversion table
| millimeter (mm) | kilometer (km) |
|---|---|
| 0.01 | 1e-8 |
| 0.1 | 1e-7 |
| 1 | 0.000001 |
| 2 | 0.000002 |
| 5 | 0.000005 |
| 10 | 0.00001 |
| 25 | 0.000025 |
| 50 | 0.00005 |
| 100 | 0.0001 |
| 1000 | 0.001 |
About these measurements
Length measures the distance between two points.
The base reference used here is the meter. One millimeter is 0.001 base units; one kilometer is 1,000 base units.
Important distinctions
International feet and inches are used. Survey feet are not included.
Precision
The converter uses stored conversion factors and floating-point arithmetic. Results display up to ten significant digits, switching to scientific notation for very small or large values. Keep the precision of your original measurement when reporting results.
Common questions
How do I convert mm to km?
Multiply the quantity in mm by 0.000001. You can also type the value into the converter above.
Can I reverse the conversion?
Yes. Use the swap button or open the kilometer to millimeter converter.
Reference
NIST Guide to the SI — conversion factors and prefix conventions. SI prefixes scale units by powers of ten; the dimension-specific notes above describe the assumptions used on this page.
