Speed Converter
Convert between km/h, mph, knots, meters per second and feet per second — for driving, running, sailing and physics homework.
Quick reference
| km/h | mph | Typical of… |
|---|---|---|
| 5 | 3.1 | Walking pace |
| 30 | 18.6 | City cycling |
| 50 | 31.1 | Urban speed limit |
| 100 | 62.1 | Highway driving |
| 900 | 559 | Airliner cruise |
Frequently asked questions
What's the quick trick for km/h to mph?
Multiply by 0.6 (the exact factor is 0.6214). So 100 km/h ≈ 62 mph and 50 km/h ≈ 31 mph.
What exactly is a knot?
One nautical mile per hour — 1.852 km/h or about 1.15 mph. It's the standard for ships and aircraft because nautical miles line up with degrees of latitude.
Why do physicists use m/s?
It's the SI unit, so equations work without conversion factors. A handy anchor: 10 m/s = 36 km/h ≈ 22.4 mph — about the top speed of a club sprinter.
Last updated: 2026-07-13