Feels-Like Temperature
Wind chill and heat index from the official formulas โ auto-chosen.
About this calculator
Temperature, wind and humidity in; the feels-like number out, computed with the same formulas forecasters use โ the North American wind chill index in the cold, the NWS heat index in the heat โ and the tool says plainly which one it used, or that neither applies and the air temperature is the honest answer.
The physics under the number
Both corrections describe your body's cooling systems being helped or sabotaged. Wind chill: your skin maintains a millimetre of warmed air, and wind strips it away โ heat leaves faster, so exposed skin cools as if the day were colder (valid below 10 ยฐC with wind above 4.8 km/h; frostbite times shorten dramatically below โ27 feels-like). Heat index: sweating is your main cooling and it only works if sweat evaporates โ humidity blocks that, so 32 ยฐC at 70% humidity stresses the body like 41. The formulas' honest limits: they're calibrated for shade and walking pace; direct sun can add several degrees to the heat index. For the plain conversion between ยฐC and ยฐF, the temperature converter is next door, and the hydration estimate matters most exactly when the heat index climbs.
Frequently asked questions
What does 'feels like' actually mean?
The air temperature that would stress your body equally in calm, shaded conditions โ wind chill models faster heat loss in cold wind; heat index models blocked sweat evaporation in humidity.
When does wind chill apply?
Below 10 ยฐC with wind over 4.8 km/h โ the official formula's validity range. Above those bounds wind barely changes heat loss, and the tool says so instead of inventing a number.
Why does humidity make heat dangerous?
Evaporating sweat is your primary cooling system, and humid air accepts less evaporation. At high humidity the body genuinely cannot shed heat at the same rate โ that's when heat illness risk climbs.
Is 'feels like' the same for everyone?
It's a model of an average adult walking in shade. Sun exposure, exertion, age and clothing all shift the real stress โ treat the number as a good warning system, not a personal measurement.