Wind Chill Index & Frostbite Risk Calculator
Enter air temperature and wind speed. The result is an index, not a forecast, medical assessment, or frostbite timer.
A QUICK WALKTHROUGH
How to use this tool
- Enter air temperature and choose °F or °C.
- Enter wind speed and choose mph, km/h, or knots.
- Review the NWS wind chill index and cold-stress band.
Formula scope
Uses the 2001 National Weather Service wind chill formula for air temperatures −50 to 50°F and wind speeds 3 to 60 mph. Outside that range the calculator stops.
Frostbite limitation
The band is a cautious cold-stress screen, not a medical diagnosis. No universal frostbite exposure time is shown because reliable timing depends on conditions and the person.
GOOD TO KNOW
Common questions
Is this a forecast?
No. It calculates an index from the values you enter.
Does it predict frostbite time?
No. There is no reliable universal timer; seek shelter and warmth when cold injury may be developing.