🚀 Speed Converter

From a US speed limit in mph to wind speed in knots while sailing: convert any speed exactly between km/h, mph, m/s and knots. Handy for travel, sports, weather reports and shipping.

Result 62.137 mph

Formula

Result = (value × from-factor) ÷ to-factor, relative to m/s

Every speed unit has a fixed conversion factor to metres per second: 1 km/h = 1 ÷ 3.6 m/s (≈ 0.277778 m/s), 1 mph = 0.44704 m/s and 1 knot = 0.514444 m/s. The calculator converts your value to m/s first and then to the target unit.

Steps

  1. 1Enter the speed you want to convert.
  2. 2Choose the unit to convert from and to: km/h, mph, m/s or knots.
  3. 3Read the exact result instantly.

Speed units in metres per second

UnitIn m/s
1 m/s1
1 km/h0.277778
1 mph0.44704
1 knot0.514444

Km/h and knots are derived units; m/s is the SI base unit of speed.

commonMistakes

  • Confusing knots (nautical miles per hour) with mph (statute miles per hour); a knot is slightly faster than one mph.
  • Forgetting to divide km/h by 3.6 when converting to m/s (a common physics-class mistake).
  • Mixing up wind speed and vehicle speed: weather reports often give wind in knots or Beaufort, not km/h.

useCases

  • Converting a US speed limit (mph) to km/h for a road trip.
  • Converting wind speed from a marine forecast (knots) into km/h.
  • Comparing a running or cycling pace in m/s with the speed shown on a traffic sign.