Rental car showing km/h when you think in mph? Wind forecast in knots? This speed converter translates between miles per hour, kilometers per hour, meters per second, knots and feet per second — type once, read all five.
How to convert mph to km/h
Multiply by 1.609. So 60 mph ≈ 96.6 km/h, 70 mph ≈ 112.7 km/h, and a 100 km/h motorway limit is about 62 mph. Going the other way, multiply km/h by 0.621 — or just remember the rough 5:8 ratio (50 mph ≈ 80 km/h).
Meters per second — the scientist's unit
Physics and weather models use m/s. The conversion to km/h is beautifully clean: multiply by 3.6 (3,600 seconds per hour ÷ 1,000 m per km). A 10 m/s wind is 36 km/h ≈ 22 mph. Sprinter's trivia: a 100 m dash in 10 s averages 10 m/s — about 22.4 mph.
What is a knot?
One knot is one nautical mile per hour — 1.852 km/h or about 1.151 mph. Aviation and shipping use knots because the nautical mile ties directly to degrees of latitude, making chart navigation cleaner. A 20-knot wind is about 23 mph; a cruise ship at 22 knots is doing roughly 25 mph.
Everyday reference speeds
Brisk walk ~5 km/h (3 mph); typical city limit 30 mph ≈ 48 km/h; US highway 65–75 mph ≈ 105–120 km/h; commercial jet cruise ~490 knots ≈ 560 mph. Converting the distances too? Use the length converter, or work out trip fuel money with the fuel cost calculator.