How to calculate speed
km/h = mph × 1.609344 · m/s = km/h ÷ 3.6
Worked example. Kilometers per hour: 96.56 km/h.
Example inputs — Speed: 60; From: Miles per hour. Starting values are illustrative.
From George Guju, founder of Calculyn · Educational calculator guidance, not professional advice.
How it works
Every unit is converted through meters per second. 1 mph = 1.609344 km/h; 1 knot = 1 nautical mile (1,852 m) per hour.
Assumptions & limitations
- Results are rounded for display.
Formula and assumptions reviewed October 2026 by the Calculyn team. How we build our calculators
Frequently asked questions
Why do boats and planes use knots?
A nautical mile matches one minute of latitude, which makes navigation math easier.