Convert a wind speed
mph
km/h
m/s
knots
ft/s
Beaufort
Common conversions
| m/s | mph | km/h | knots | Beaufort |
|---|---|---|---|---|
| 1 | 2.2 | 3.6 | 1.9 | 1 · Light Air |
| 5 | 11.2 | 18.0 | 9.7 | 3 · Gentle Breeze |
| 10 | 22.4 | 36.0 | 19.4 | 5 · Fresh Breeze |
| 15 | 33.6 | 54.0 | 29.2 | 7 · Near Gale |
| 20 | 44.7 | 72.0 | 38.9 | 8 · Gale |
| 25 | 55.9 | 90.0 | 48.6 | 10 · Storm |
| 30 | 67.1 | 108.0 | 58.3 | 11 · Violent Storm |
| 40 | 89.5 | 144.0 | 77.8 | 12 · Hurricane |
| 50 | 111.8 | 180.0 | 97.2 | 12 · Hurricane |
Calculated with the factors of the NWS El Paso "Wind Speed Conversion" calculator; Beaufort force from the NWS Miami table.
The factors
- m/s to mph: multiply by 2.23694. mph to m/s: multiply by 0.44704.
- mph to km/h: multiply by 1.609344. km/h to mph: divide by 1.609344.
- mph to knots: multiply by 0.8689762. knots to mph: multiply by 1.1507794.
- m/s to km/h: multiply by 3.6 (one hour has 3,600 seconds, one kilometer 1,000 meters).
Which unit where? U.S. forecasts give wind in mph, aviation and marine reports in knots, and many weather apps and stations outside the U.S. in km/h or m/s. To see the wind where you are right now, use our live wind speed tool; to see what a speed means outside, the Beaufort scale.
Quick answers
How do I convert m/s to mph?
Multiply by 2.23694. For example, 10 m/s is about 22.4 mph, force 5 "Fresh Breeze" on the Beaufort scale.
How many mph is 1 knot?
1.1507794 mph, the factor the NWS calculator uses. 20 knots is about 23 mph.
How fast is 30 km/h in mph?
About 18.6 mph (30 ÷ 1.609344): force 4, "Moderate Breeze".
Sources: NWS El Paso: Wind Speed Conversion · NWS Miami: Beaufort Wind Scale
