Calculate Wind Chill
This calculator uses the standard wind chill temperature model. In metric form:
WCT(°C) = 13.12 + 0.6215T − 11.37V0.16 + 0.3965T·V0.16
where T is air temperature in °C and V is wind speed in km/h. The imperial form is equivalent and is also computed for reference.
Typical guidance: use when air is cold and wind is noticeable.
- Enter the current air temperature and select its unit.
- Enter wind speed and choose the correct wind unit.
- Select the output unit and rounding preference.
- Press Submit to see the wind chill result above.
- Use the CSV or PDF buttons to export your result.
| Air Temp (°C) | Wind (km/h) | Wind Chill (°C) | Notes |
|---|---|---|---|
| -5 | 20 | -12.0 | Cool day with steady breeze |
| -10 | 30 | -19.6 | Risk increases with longer exposure |
| -20 | 40 | -34.2 | Very cold; limit time outdoors |
| 0 | 10 | -3.3 | Mild cold; wind still matters |
These examples are rounded and for learning only.
1) What wind chill represents
Wind chill estimates how cold exposed skin feels when wind speeds up heat loss. It is not a new air temperature; it is an equivalent cooling effect for outdoor planning. Faster wind increases convective cooling, so the same air temperature can feel much colder.
2) When the model is valid
Standard wind chill equations target cold, breezy weather with wind measured near 10 m height. Results are most meaningful when air temperature is at or below 10 °C and wind speed is above 4.8 km/h. Outside these ranges, real “feels like” conditions can differ.
3) Inputs and unit handling
Air temperature and wind speed control the output. This tool accepts °C/°F and wind in km/h, m/s, mph, or knots. It converts inputs to a consistent internal system, then applies the matching metric or imperial wind chill equation.
4) Wind speed benchmarks you can picture
As a field guide, 10 km/h is a light breeze, 20–30 km/h is a steady wind, and 40 km/h can feel harsh. If you only know gusts, sustained wind is usually lower. Use sustained wind for planning; gusts explain brief colder bursts.
5) Risk ranges and exposure timing
Safety charts often group risk by wind chill. Near −10 °C, discomfort increases and skin cools quickly. Around −27 °C, frostbite risk rises with longer exposure, especially on fingers and ears. Around −39 °C and below, frostbite can occur in minutes, so reduce time outdoors and monitor numbness.
6) Clothing decisions from the result
Use wind chill to choose layers. A windproof outer shell cuts convective loss, while insulating layers trap warm air. Cover extremities and keep inner layers dry; moisture increases heat loss. Add insulation during rest stops.
7) Travel and work planning
Treat wind chill as a planning number. If the result is far below freezing, shorten outdoor tasks and schedule warm-up breaks. For driving, remember that breakdowns create outdoor exposure. For field work, set time limits, rotate duties, and use buddy checks. Carry spare gloves and a hat for changing conditions. Keep batteries warm too.
8) Limitations and best practices
Wind chill does not include sunshine, clothing type, body size, or activity level, and it does not measure hypothermia directly. Use it with local forecasts and precipitation. When uncertain, assume higher risk, reduce exposure time, and watch skin and alertness.
1) Is wind chill the same as air temperature?
No. Wind chill is an equivalent cooling effect on exposed skin. Air temperature is what a thermometer reads; wind chill estimates how cold it feels as wind increases heat loss.
2) Why does wind chill equal air temperature sometimes?
At very low wind speeds, forced convection is small, so cooling is close to calm-air conditions. The calculated wind chill approaches the actual air temperature.
3) Can wind chill ever be warmer than the air?
No. Wind chill represents increased cooling from wind, so it will be equal to or colder than the air temperature within the valid ranges of the model.
4) Should I enter gust speed or sustained wind?
Sustained wind is recommended because it better represents ongoing exposure. Gusts can cause short spikes in cooling, but sustained wind usually gives a steadier planning value.
5) What equation does the calculator use?
It uses the standard wind chill temperature model with a wind-speed exponent of 0.16. The calculator applies the metric or imperial form after converting your units.
6) Does wind chill apply indoors or inside a vehicle?
Not directly. Wind chill is designed for outdoor exposure to moving air. Indoors or in a heated vehicle, airflow and temperature differ, so the estimate may not reflect comfort or risk.
7) What’s the quickest way to reduce wind chill risk?
Block wind and cover skin. A windproof outer layer plus insulated gloves and face protection reduce heat loss fast. Shorten exposure time and take warm-up breaks in severe conditions.