A heat index is an index that combines air temperature and relative humidity in an attempt to determine the human-perceived equivalent temperature; "how hot it feels." The result is also known as the "felt air temperature" or "apparent temperature." For example, when the temperature is 90°F with very high humidity, the heat index can be about 106°F.
This calculator calculates the heat index or apparent temperature.

The calculator takes as input the air temperature and dew point temperature or relative humidity, and calculates the heat index. This information can be used to make informed decisions related to outdoor activities, such as scheduling work or leisure activities, and to monitor potential heat-related health risks, especially during extreme heat events.

How to use this calculator:
1. Choose the appropriate calculator
2. Choose the temperature unit between degrees Fahrenheit, degrees Celsius. If you worry about the conversion, we have "Temperature Converter" tool that helps you to convert among different temperature units quickly.
3. Enter your dew point temperature or relative humidity (%)
4. "Calculate" button to estimate the heat index temperature.
5. The heat index temperature will be displayed in different temperature units.
6. There is short instruction / warning depend on the value of heat index.

If you experience problems with the “Heat Index Calculator - How to”, please contact us at dotri84@gmail.com.