Heat Index Calculator
Calculate how hot it really feels
°F
80°F
112°F
%
13%
85%
Heat Index Result
87.9°F
Caution: Fatigue possible
Heat Index Guide
< 80°F: No significant effect
80-90°F: Caution – fatigue possible
90-105°F: Extreme caution – heat stroke possible
> 105°F: Danger – heat stroke likely
The heat index is a measure of how hot it really feels when relative humidity is factored in with the actual air temperature.