How to Convert Kilometres to Nanometres (km to nm)
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. This guide shows how to convert kilometres into nanometres by hand, with examples and a quick-reference table.
The conversion
To convert kilometres to nanometres, multiply the value by 1.000000e+12. To go the other way, divide by the same number (or multiply by 1.000000e-12). For a quick estimate, multiply by about 1,000,000,000,000.
Nanometres = kilometres × 1.000000e+12
Worked examples
- 3 km = 3.000000e+12 nm
- 12.5 km = 1.250000e+13 nm
- 75 km = 7.500000e+13 nm
Kilometres to Nanometres table
| Kilometres | Nanometres |
|---|---|
| 1 km | 1,000,000,000,000 nm |
| 2 km | 2.000000e+12 nm |
| 5 km | 5.000000e+12 nm |
| 10 km | 1.000000e+13 nm |
| 20 km | 2.000000e+13 nm |
| 25 km | 2.500000e+13 nm |
| 50 km | 5.000000e+13 nm |
| 100 km | 1.000000e+14 nm |
| 250 km | 2.500000e+14 nm |
| 500 km | 5.000000e+14 nm |
| 1,000 km | 1.000000e+15 nm |
Common questions
Is km to nm exact?
The factors used here are the internationally defined values where they exist; results are rounded for display only.
How do I convert back?
Use the Nanometres to Kilometres converter.
Mistakes to avoid
Mixing similar-sounding units
US and imperial gallons, pints and tons are different sizes, and decimal kilobytes differ from binary kibibytes.
Dropping the units
A bare number without a unit is easy to misread later. Always write the unit with the result.
Multiplying when you should divide
Converting to a smaller unit gives a bigger number, and converting to a larger unit gives a smaller one. If your answer moves the wrong way, you have inverted the factor.
Background
Unit conversion is simply multiplication by a fixed ratio. The ratio between two units of the same quantity never changes, so once you know it you can convert any value in either direction.
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.
A conversion table is handy for common values, but a calculator is faster and avoids interpolation errors for anything in between.
For any value, use the Kilometres to Nanometres Converter or browse all length converters.
Run your own numbers: Kilometres to Nanometres Converter