Heat Index Calculator
Humidity is the killer multiplier. Official Rothfusz computation with edge-case corrections.
Heat index (feels like)
113.1°F
- Category
- Danger — heat illness likely
How the Heat Index Calculator works
The calculation follows the standard method used across the US — no shortcuts, no hidden assumptions. Here is exactly what happens behind the scenes:
Frequently Asked Questions
How does the Heat Index Calculator work?
Enter your numbers above and results update instantly using standard formulas, computed entirely on your device.
Is the Heat Index Calculator free to use?
Yes — completely free with no signup required, and it works on phones, tablets, and desktops.
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