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LunaCalc

Conversion

Speed Conversion

Convert km/h, m/s, mph and other speed units.

Calculator
Imperial/US
Metric
Other
Run pace

About this calculator

This speed converter switches between m/s, km/h, mph, and knots with exact factors.

Formula notes

1 m/s = 3.6 km/h ≈ 2.237 mph ≈ 1.944 knots.

Worked examples

  1. Example: 100 km/h ≈ 27.78 m/s ≈ 62.14 mph ≈ 54 knots.
  2. A speed of 10 m/s equals 36 km/h and approximately 22.37 mph.

How to use it

  1. Enter the speed in the unit you have.
  2. Read all other unit equivalents.
  3. Use knots for aviation and marine contexts.

Frequently asked questions

Why is a knot used at sea?

One knot is one nautical mile per hour, and nautical miles match latitude minutes on charts.

Is mph exact relative to km/h?

Yes. 1 mile = 1.609344 km exactly, so 100 km/h = 62.137 mph.

Limits and interpretation

  • The conversion treats speed as a scalar and does not preserve direction, acceleration, or changing velocity over time.
  • Average speed over a trip can differ materially from an instantaneous instrument reading.

References