Heat index
Calculate Heat index instantly with the exact formula and a worked example.
Heat index
Temp, °F
Humidity, %
Heat index
99.6777°F
HI °F
99,7
HI °C
37,6
More about: Heat index
What it calculates
The “Heat index” calculator computes Heat index in °F from 2 parameters: temp, °f, humidity, %.
A standard physics formula used in educational and engineering tasks.
Example calculation
With parameters Temp, °F = 90, Humidity, % = 60 the result is 99.68 °F (Rothfusz (NWS)).
How to use
- Enter temp, °f and humidity, % — each field above is adjustable with a slider.
- Heat index (°F) is calculated automatically as you type.
- Check the worked example below to see the formula applied to real numbers.
- Copy the result or bookmark this calculator.
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FAQ
How is Heat index calculated?
The Heat index calculator computes Heat index (in °F) from temp, °f, humidity, %. Enter your values above and the exact formula is applied instantly; a worked example with real numbers is shown below.
Is the Heat index calculator free?
Yes. It is completely free, needs no signup, runs entirely in your browser, and sends no data to any server.
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