21 mph = 18.25 knots
21 miles per hour is equal to approximately 18.25 knots.
More precise conversion
21 mph = 18.2485010799 knots
How to convert 21 mph to knots
Multiply the speed in MPH by approximately 0.868976242.
21 × 1609.344 ÷ 1852 = 18.2485010799 knots
The commonly displayed result, 18.25 knots, is rounded to two decimal places. The more precise result is rounded to 10 decimal places where needed.
Also equals
- Kilometers per hour
- 33.796224 km/h
- Meters per second
- 9.38784 m/s
- Feet per second
- 30.8 ft/s
- Centimeters per second
- 938.784 cm/s
MPH to knots converter
Nearby MPH to knots conversions
About MPH and knots
MPH means miles per hour, and one international mile is exactly 1,609.344 meters. A knot is one nautical mile per hour, and one international nautical mile is exactly 1,852 meters.