mph → km/h converter
An international mile is exactly 1.609344 kilometres. Multiply miles per hour by that factor to obtain kilometres per hour. The nautical mile used by knots is 1.852 kilometres, so knots and mph are different. This calculation changes units and does not measure speed.
Conversion formula
km/h = mi/h × (25146/15625)
Reference values
| mi/h | km/h |
|---|---|
| 1 | 1.609344 |
| 5 | 8.04672 |
| 10 | 16.09344 |
| 100 | 160.9344 |
| 500 | 804.672 |
| 1000 | 1609.344 |
The table uses 12 significant digits. The ≈ mark identifies display rounding. Enter another value in the converter and choose up to 30 significant digits when needed. More displayed digits do not improve the uncertainty of the original measurement.