How to Convert km/h to mph and Other Speed Units
Enyong Carinton Tegum·
November 12, 2025·
1 min read
Speed limits in mph when your car reads km/h (or vice versa) can be genuinely important to get right. Here are the conversions for the units you'll actually meet.
The key factors
- 1 km/h = 0.621 mph — so multiply km/h by ~0.62 for mph.
- 1 mph = 1.609 km/h — multiply mph by ~1.61 for km/h.
- 1 m/s = 3.6 km/h — handy for physics.
- 1 knot ≈ 1.852 km/h — for aviation and sailing.
The mental shortcut
km/h to mph: multiply by 6 and drop a zero (100 km/h → 600 → 60 mph; actual 62). Quick enough to sanity-check a speedometer abroad.
Convert instantly
Our free speed converter handles km/h, mph, m/s, knots and more. For distance units behind the speed, see the length converter.
Bottom line
km/h × 0.62 = mph; mph × 1.61 = km/h. The "×6, drop a zero" trick gets you close for driving. When the speed limit is legally binding, let a converter confirm it exactly.
