Wind Chill Calculator

Estimate how cold it actually feels outdoors when wind lowers the perceived temperature. Enter the air temperature and sustained wind speed to see the National Weather Service wind chill index in degrees Fahrenheit.

Air temperature measured in degrees Fahrenheit.
Sustained wind speed in miles per hour, measured at 5 ft (1.5 m) above ground.

Approximate guideline; extreme weather can be dangerous despite calculations.

Examples

  • 30°F with a 10 mph breeze feels like 21.3°F.
  • 10°F with 25 mph winds feels like -9.4°F.
  • -5°F with 40 mph gusts feels like -35.4°F.

FAQ

When is this formula valid?

For temperatures at or below 50°F and winds above 3 mph.

Does sunshine affect wind chill?

The formula assumes shady conditions without direct sun.

What units are required?

Temperature in Fahrenheit and wind speed in mph.

What if wind is calm?

For winds under 3 mph, wind chill equals the air temperature.

How quickly can frostbite occur?

At wind chills of -18°F or colder, exposed skin can freeze in 30 minutes or less. The calculator helps identify when to limit outdoor exposure.

Additional Information

  • Formula applies when temperature is 50°F or below and wind speed is above 3 mph.
  • Wind chill estimates perceived temperature on exposed skin under shady conditions.
  • Convert the result to Celsius by subtracting 32 and multiplying by 5/9 after calculation.
  • Layering clothing, wearing windproof gear, and covering extremities help reduce frostbite risk.

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