Wind Chill Calculator
See how cold it really feels on your skin by combining air temperature and wind speed. Supports °F/°C and mph/km/h/m/s, with risk level and frostbite time estimates.
Wind Chill – Feels Like Temperature
Feels like temperature
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Cold stress & frostbite risk
Risk level: —
Estimated frostbite time on exposed skin: —
Based on standard wind chill safety guidance for healthy adults. Individual risk may vary.
Quick wind chill lookup (°F & mph)
Common combinations of air temperature and wind speed. Use the calculator above for any custom value.
| Air temp (°F) | 5 mph | 10 mph | 20 mph | 30 mph | 40 mph |
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What is wind chill?
Wind chill is the apparent temperature your body feels on exposed skin when you combine the effects of cold air and wind. Moving air strips away the thin layer of warm air next to your skin, causing heat to be lost more quickly than in still air, so it feels colder than the actual air temperature.
Meteorological services such as the NWS in the US and Environment Canada use a standardized wind chill index to communicate cold stress and frostbite risk.
Wind chill formula
The current North American wind chill index (used in the US and Canada) is defined for air temperatures at or below 50°F (10°C) and wind speeds above 3 mph (5 km/h).
Formula in Fahrenheit and mph
\( WCT = 35.74 + 0.6215T - 35.75V^{0.16} + 0.4275T V^{0.16} \)
- WCT = wind chill temperature (°F)
- T = air temperature (°F)
- V = wind speed (mph)
Formula in Celsius and km/h
\( WCT = 13.12 + 0.6215T - 11.37V^{0.16} + 0.3965T V^{0.16} \)
- WCT = wind chill temperature (°C)
- T = air temperature (°C)
- V = wind speed (km/h)
Our calculator automatically converts between units (mph, km/h, m/s; °F and °C) and applies the correct version of the formula within its valid range.
When is wind chill important?
Wind chill matters whenever you have:
- Cold air (typically below 50°F / 10°C), and
- Noticeable wind (above about 3 mph / 5 km/h), and
- Exposed skin (face, hands, ears, etc.).
In these conditions, your body loses heat faster, increasing the risk of hypothermia and frostbite, especially at low wind chill values.
Wind chill risk levels and frostbite time
The table below summarizes typical risk categories used by weather services.
| Wind chill (°F) | Wind chill (°C) | Risk level | Approx. frostbite time* |
|---|---|---|---|
| > 0°F | > −18°C | Low to moderate | Frostbite unlikely for most people |
| 0 to −19°F | −18 to −28°C | Increased risk | ~30 minutes on exposed skin |
| −20 to −34°F | −29 to −36°C | High | 10–30 minutes |
| ≤ −35°F | ≤ −37°C | Extreme | ≤ 10 minutes (as little as 5 minutes) |
*Approximate times for healthy adults with dry skin and typical clothing. Children, older adults, and people with medical conditions may be at higher risk.
How to stay safe in low wind chill
- Layer your clothing: Use moisture-wicking base layers, insulating mid-layers, and a windproof outer shell.
- Cover exposed skin: Hat, scarf, face mask, and insulated gloves or mittens are essential.
- Stay dry: Wet clothing dramatically increases heat loss.
- Limit time outdoors: Especially when wind chill drops below 0°F (−18°C).
- Watch for warning signs: Numbness, tingling, pale or waxy skin, confusion, or shivering that stops.
FAQ
Why does wind make it feel colder?
Your body warms a thin layer of air next to your skin. Wind constantly replaces this warm layer with colder air, increasing convective heat loss. The stronger the wind, the faster you lose heat, and the colder it feels.
Can wind chill make objects colder than the air?
No. Wind chill only affects living beings that produce heat. Inanimate objects like cars or pipes cannot cool below the actual air temperature, although wind can make them cool down to air temperature faster.
Does wind chill affect indoor temperatures?
Not directly. Wind chill is defined for exposed skin outdoors. However, strong winds can increase heat loss from buildings if they are poorly insulated or drafty, making interiors feel colder.
Why is there no wind chill on very warm days?
The standard wind chill formula is only defined for temperatures at or below 50°F (10°C). At higher temperatures, wind can actually make you feel cooler by enhancing sweat evaporation, but this is usually described using heat index or apparent temperature, not wind chill.