Wind Chill Calculator (NWS Formula)
Enter the air temperature and the sustained wind speed from your forecast to see how cold it will feel on exposed skin. The math is the National Weather Service wind chill formula, the same one behind the NWS wind chill chart.
This is an estimate, not a forecast or medical advice. The NWS formula assumes no sunshine (bright sun can make it feel 10 to 18 °F warmer) and is defined only at 50 °F or below with winds above 3 mph. Follow your local NWS cold weather alerts, and be even more cautious with children, older adults and anyone in poor health.
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Results
| Air temperature used | — |
|---|---|
| Wind speed used | — |
| Wind chill (°F, rounded) | — |
| Wind chill (°C) | — |
| Frostbite possible? | — |
Formula used
- Wind chill (°F) = 35.74 + 0.6215 T − 35.75 V0.16 + 0.4275 T V0.16, where T is the air temperature in °F and V is the wind speed in mph (National Weather Service).
- Defined only when T is 50 °F or lower and V is above 3 mph. Celsius and km/h inputs are converted first (°F = °C × 9/5 + 32; mph = km/h ÷ 1.609344).
- Frostbite check: the NWS says you can get frostbite only if the actual air temperature is below freezing (32 °F). A below-freezing wind chill on an above-freezing day doesn't cause frostbite, but hypothermia is still possible.
Worked example (from the NWS)
- Air temperature 0 °F with a 15 mph wind gives a wind chill of −19 °F. The NWS says exposed skin can freeze in 30 minutes at that wind chill.
For warning signs and first aid, read our wind chill, frostbite and hypothermia guide.
Sources
Sources checked October 29, 2026.