Speed Converter

How it works

Convert travel, wind, and marine speeds quickly.

When this question comes up

Speed conversion shows up in driving abroad, running and cycling logs, wind forecasts and marine weather. The unit people misread most often is the knot: it is one nautical mile per hour, roughly 15% faster than mph, and not the same thing.

Rules and limits

• 1 mile per hour = 1.609344 km/h and 1 knot = 1.852 km/h, both exact.
• A knot is one nautical mile per hour, which is why it is used for wind and marine speeds.

Worked example

100 km/h = 62.137119 mph · 1 kn = 1.852 km/h

Checking the result by hand

1 m/s = 3.6 km/h exactly, so km/h to m/s is a division by 3.6. 1 mph = 1.609344 km/h and 1 knot = 1.852 km/h. For a quick check, 100 km/h is about 62 mph, and a wind of 30 knots is roughly 55 km/h.

FAQ

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