Convert kilometers per hour to miles per hour — and back — with the exact factor (1 mph = 1.609344 km/h). Loads with km/h → mph preselected; type a speed and read it in the other system instantly.
The formula
mph = km/h ÷ 1.609344 · km/h = mph × 1.609344. Quick check: mph is roughly 60% of km/h — 100 km/h → ≈62 mph. It’s the miles-to-km factor with the hours canceled, which is why the miles to km page shows the same 1.609344.
Speed limit cheat sheet
| km/h | mph | Where you see it |
|---|---|---|
| 30 | 18.6 | School zones (EU) |
| 50 | 31.1 | Urban default (EU) |
| 80 | 49.7 | Rural roads |
| 100 | 62.1 | Many motorways |
| 110 | 68.4 | AU/CA highways |
| 120 | 74.6 | ES/PT/ZA motorways |
| 130 | 80.8 | FR/IT motorways |
Rental cars, treadmills, wind
Driving abroad is the classic case: the posted 130 on a French autoroute is 81 mph, and a US-market car’s speedometer makes you do the math at speed — memorize 50/80/100/130. Fitness equipment ships in the market’s unit; the treadmill FAQ has the pace anchors so a holiday run doesn’t turn into a tempo session. Weather: metric forecasts give wind in km/h, US forecasts in mph, marine and aviation in knots — the 1.852 factor is its own unit in the unit converter’s Speed category, alongside m/s for physics homework.
Private by design
The conversion runs on your device as you type — no server round-trip, no logging. Pair it with Celsius to Fahrenheit and you’re travel-ready.