Find how cold it really feels. This free wind chill calculator combines air temperature and wind speed (°F/mph or °C/km/h) using the NWS formula, with the feels-like temperature and frostbite-risk notes.
Enter the air temperature and wind speed. Wind chill is most meaningful in cold, windy conditions; outside that range it’s shown as an approximation.
Based on the US National Weather Service wind chill formula. Wind chill affects how quickly exposed skin loses heat; it does not lower the temperature of objects below the actual air temperature.
How the Wind Chill Calculator Works
Wind chill converts air temperature and wind speed into a single “feels like” number that reflects how quickly exposed skin loses heat. The calculator uses the official U.S. National Weather Service formula, which is only meant to apply in genuinely cold, breezy conditions.
Formula: Wind Chill (°F) = 35.74 + 0.6215×T − 35.75×V^0.16 + 0.4275×T×V^0.16, where T is air temperature in °F and V is wind speed in mph. This formula only runs when T is 50°F or below and V is at least 3 mph; outside that range the calculator returns the actual air temperature as an approximation, since wind chill isn’t meaningful in mild or calm conditions. Celsius and km/h entries are converted to °F and mph before the formula runs.
- T (Air temperature) — the value entered in the Air temperature field, in °F or °C depending on the Units toggle
- V (Wind speed) — the value entered in the Wind speed field, in mph or km/h
- Units toggle — switches the whole calculator between F · mph and C · km/h, converting inputs before the formula is applied
Example Scenarios
| Temperature (°F) | Wind Speed (mph) | Wind Chill (°F) |
|---|---|---|
| 30 | 10 | 21 |
| 20 | 15 | 6 |
| 10 | 20 | -9 |
| 0 | 25 | -24 |
| -10 | 30 | -39 |
Wind Chill Calculator FAQ
At what temperature does wind chill stop applying?
The National Weather Service formula used here is only valid at 50°F or below with wind of at least 3 mph. Above 50°F or in calm air, wind doesn’t meaningfully change how cold the air feels, so the calculator just shows the actual temperature.Why does the wind chill number change so little above 25-30 mph?
Because wind speed enters the formula raised to the power 0.16, a small exponent that flattens out quickly. Doubling the wind speed from say 15 to 30 mph cools the feels-like temperature noticeably less than doubling it from 3 to 6 mph.Can wind chill actually make skin cold faster than the thermometer suggests?
Yes — wind chill describes how fast exposed skin loses heat, and at very low wind chill values frostbite can develop on exposed skin in well under 30 minutes. It does not lower the temperature of water, car engines, or other objects below the actual air temperature, only how quickly living tissue cools.Does wind chill affect how fast a car engine or pipes freeze?
No. Wind chill measures heat loss from exposed skin, not a physical drop in air temperature. A parked car’s antifreeze or an exposed pipe freezes based on the actual air temperature, not the wind chill value.What’s the difference between the metric and imperial results?
They describe the same feels-like temperature, just converted — the calculator always runs the NWS formula in Fahrenheit and mph internally, then converts your Celsius or km/h entries in, and the result back out, if you’ve selected metric units.How is wind chill different from heat index?
Wind chill measures how much colder moving air makes cold weather feel, while heat index measures how much hotter humid air makes warm weather feel. They use separate formulas and apply in opposite temperature ranges.Related Calculators
For the opposite scenario, the heat index calculator shows how humidity makes warm weather feel hotter rather than colder. If you’re working with other weather- or physics-related figures, the pressure converter and the speed of sound calculator (which is also affected by air temperature) can be useful alongside wind chill.