Heat Index Calculator
Calculate the apparent temperature (feels-like heat index) based on air temperature and relative humidity using the NWS Rothfusz equation.
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Calculator insights
What this calculator does
Heat Index Calculator helps you quickly estimate calculate the apparent temperature (feels-like heat index) based on air temperature and relative humidity using the nws rothfusz equation. with clean output and clear next steps.
How the calculation works
Enter Air Temperature, Relative Humidity and this calculator uses standard formulas to determine Heat Index (°F) and Heat Index (°C). The output is displayed immediately in a user-friendly format.
Example calculation
For example, enter realistic values into the Heat Index Calculator to see how the calculator produces Heat Index (°F) and Heat Index (°C) that you can use for planning and comparison.
Disclaimer
The calculations provided by this website are for informational purposes only and should not be considered financial, legal, tax, or professional advice.
Frequently Asked Questions
What heat index is dangerous?
NWS heat index categories: Caution: 80-90°F, Extreme Caution: 91-103°F, Danger: 103-124°F, Extreme Danger: 125°F+.