Wind Speed Converter
Convert a nonnegative wind speed between meters per second, kilometers per hour, miles per hour, knots and feet per second using defined units.
Convert a wind-speed reading into the units used by another forecast, instrument or report. Enter one nonnegative speed and obtain meters per second, kilometers per hour, miles per hour, knots and feet per second together. The conversion changes only the unit, so the source measurement’s meaning and precision remain important.
How to use this tool
- Enter the wind speed as a nonnegative number.
- Select the unit attached to that reading.
- Read the five equivalent speeds and keep the appropriate number of significant figures.
- Retain the source’s gust or sustained-wind label when using the converted value elsewhere.
Formula
Output speed = input speed × input factor in m/s ÷ output factor in m/s
Defined factors are 1 mph = 0.44704 m/s, 1 ft/s = 0.3048 m/s, 1 km/h = 1/3.6 m/s, and 1 knot = 1852/3600 m/s. The mile and foot are international units. Numerical output is rounded for display.
Example
A wind of 10 m/s is 36 km/h. Separately, 1 knot is exactly 1.852 km/h, and 1 mph is exactly 1.609344 km/h. These examples follow directly from the distance and hour definitions.
Frequently asked questions
Are knots a distance or a speed?
A knot is a speed: one international nautical mile per hour. A nautical mile by itself is a distance of exactly 1,852 meters, so the two labels are not interchangeable.
Can I compare a converted gust with sustained wind?
The units may match, but their averaging intervals still differ. Keep gusts and sustained observations separate and check the source’s measurement method before comparing conditions.
Does this calculate a storm category or wind pressure?
No. It converts scalar speed only. Storm classifications depend on their published measurement rules, and pressure calculations require additional physical assumptions such as air density.
Sources
Last updated: 2026-10-30