Wind Chill Calculator
Find out how cold it really feels once you factor in the wind, using the National Weather Service wind chill formula.
This is the official NWS wind chill from 2001: 35.74 + 0.6215T − 35.75V^0.16 + 0.4275T·V^0.16, with T in °F and V in mph. It estimates how quickly exposed skin loses heat.
How it works
Wind strips away the thin layer of warm air your body builds up against your skin, so a breezy 20°F day drains heat far faster than a still one. Wind chill puts a number on that — how cold the moving air actually feels.
The formula here is the one North America adopted in 2001: 35.74 + 0.6215T − 35.75V^0.16 + 0.4275T·V^0.16, where T is the temperature in °F and V is the wind speed in mph. Type in both and you'll get the feels-like number.
It only applies when it's 50°F (10°C) or colder and the wind is above 3 mph — the conditions where wind chill matters. In warmer or calmer air, the concept doesn't really hold, so the tool will flag that for you.
Frequently asked questions
What's the wind chill at 0°F with a 20 mph wind?
About −22°F. That's cold enough for frostbite on exposed skin in roughly 30 minutes, which is exactly why the wind chill warning exists — the air temperature alone understates the risk.
Does wind chill affect my car or pipes?
No. Wind chill only describes heat loss from warm objects like your body. Water pipes and engine blocks can't cool below the actual air temperature, so wind chill doesn't make them freeze faster.
Why is there a wind speed limit on the formula?
Below about 3 mph the air is nearly still and the wind chill effect is negligible, so the formula isn't defined there. Above the threshold, faster wind keeps carrying heat away and the feels-like temperature keeps dropping.