What does the Heat Index Calculator work out?

How hot it feels with humidity. It is one of the Everyday & Tech tools on Mondo Knows.

How is the Heat Index Calculator calculated?

You get an instant answer with the working shown underneath.

Do I need to sign up, and is my data stored?

No sign-up, and nothing you type is sent anywhere. The calculation runs in your own browser, so the figures stay on your device and the page works offline once loaded.

Mondo Knows Tools

Heat Index Calculator

How hot it feels with humidity. Use the free heat index calculator below to get an instant answer, with the formula shown so you can check the maths and trust the result. Free, private, and no sign-up.

Temperature

Relative humidity

Mondo says

Feels like

113.1 F

Risk levelDanger

In Celsius45.1 C

Heat Index Calculator: common questions

What does the Heat Index Calculator work out?: How hot it feels with humidity. It is one of the Everyday & Tech tools on Mondo Knows.
How is the Heat Index Calculator calculated?: You get an instant answer with the working shown underneath.
Do I need to sign up, and is my data stored?: No sign-up, and nothing you type is sent anywhere. The calculation runs in your own browser, so the figures stay on your device and the page works offline once loaded.

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Facts that connect to the heat index calculator

Short, sourced facts that point back to this tool.

Death Valley holds the record for the highest recorded air temperatureAn air temperature of 56.7 degrees Celsius was recorded at Furnace Creek in Death Valley in July 1913.The Danakil Depression is one of the hottest and lowest places on EarthLocated in northern Ethiopia, the Danakil Depression sits 125 metres below sea level.Lightning bolts are hotter than the surface of the SunA single electrical strike can heat surrounding air to thirty thousand degrees Celsius Extremophile archaea thrive in boiling acid and deep hydrothermal ventsSpecialized cell membranes and stable enzymes allow archaea to inhabit hostile environments

Estimates for general guidance only. This is not financial, medical or legal advice. Everything runs in your browser and nothing you type is stored.