Heat Index Calculator
Calculate the apparent temperature (heat index) based on air temperature and humidity. Find out how hot it really feels and get safety recommendations.
Use Relative Humidity
This calculator estimates the temperature felt by the body as a result of air temperature and relative humidity.
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Use Dew Point Temperature
About Heat Index
The heat index, also known as the apparent temperature, is what the temperature feels like to the human body when relative humidity is combined with air temperature. This has important considerations for the human body's comfort and health.
Why Heat Index Matters:
- When humidity is high, sweat doesn't evaporate as quickly
- The body can't cool itself as efficiently
- This makes it feel hotter than the actual air temperature
- High heat index values can lead to heat-related illnesses
Safety Tips:
- Stay hydrated - drink water regularly
- Take frequent breaks in shaded or air-conditioned areas
- Wear light-colored, loose-fitting clothing
- Avoid strenuous activities during peak heat hours
- Monitor for signs of heat exhaustion or heat stroke