Wind Chill Calculator
Calculate the wind chill temperature from air temperature and wind speed.
Try an example
6.2°F
About this calculator
What Is Wind Chill?
In winter, the temperature your body feels is often lower than the actual air temperature. That "feels like" value is the wind chill: an estimate of how cold the air feels on exposed skin once wind is taken into account. Skin loses heat through conduction, convection and radiation, and wind speeds up the convection part by carrying away the thin layer of warm air that normally surrounds the body. This wind chill calculator estimates the felt temperature from the air temperature and wind speed, and it works for temperatures between −50°F and 50°F.
The Wind Chill Formula
The modern formula, adopted by the U.S. and Canadian weather services in 2001, is WCT = 35.74 + 0.6215 T − 35.75 V0.16 + 0.4275 T V0.16, with T in °F and V as wind speed in mph. At 20°F with a 15 mph wind, the wind chill is about 6°F. The formula assumes a person walking in the wind, and it is not valid for wind below about 3 mph or temperatures above 50°F.
Worked Example
At 20°F with a 15 mph wind, the wind chill is about 6.2°F — the air feels roughly 14 degrees colder than the thermometer alone suggests.
Why Wind Chill Matters for Safety
- Frostbite risk: at wind chills below about −18°F (−28°C), exposed skin can freeze in 30 minutes or less, and at much lower values in just minutes.
- Hypothermia: prolonged exposure to cold and wind can drop body temperature to dangerous levels, even at temperatures above freezing.
- Vulnerable people: children, older adults and people with circulation problems feel the effects sooner.
Wind chill affects people and animals, but not objects: a car engine or a water pipe will only cool down to the actual air temperature, though wind helps it get there faster.
How to Dress for Wind Chill
Wear windproof outer layers, insulating middle layers and moisture-wicking base layers; cover your head, hands, ears and face; and keep clothing dry, since wet fabric loses heat quickly. Warm up often and limit the time outside when the wind chill is severe.
Related Weather Calculators
The opposite problem is in summer — the Heat Index Calculator estimates how hot it feels in humid weather, and the Dew Point Calculator explains the moisture behind it. Convert temperatures and wind speeds between units with the Unit Conversion Calculator.
Worked example
At 20°F with a 15 mph wind, the wind chill is about 6.2°F — the air feels roughly 14 degrees colder than the thermometer reading.
Frequently asked questions
Why doesn't wind chill apply above 50°F?
The formula was developed for cold-weather conditions, where wind meaningfully accelerates heat loss from skin. Above 50°F, wind doesn't have the same cooling effect, so the National Weather Service doesn't define a wind chill value there.
Is wind chill just about comfort, or is it a real temperature?
It's not a literal air temperature — it's an estimate of how quickly exposed skin loses heat, expressed in equivalent-feeling degrees. It's meaningful for assessing frostbite risk, not for things like how fast water would freeze.
