Heat Index Calculator
This calculator estimates the temperature felt by the body as a result of air temperature and relative humidity.
Modify the values and click the calculate button to use
Use Relative Humidity
Heat Index Temperature: — °C (— °F, — K)
Use Dew Point Temperature
Heat Index Temperature: — °C (— °F, — K)
Relative Humidity: — %
What is Heat Index?
The heat index (or "feels-like" temperature) combines air temperature and humidity to measure how hot it actually feels. High humidity reduces sweat evaporation, making it harder for your body to cool itself. For example, at 83°F with 70% humidity, it may feel like 88°F.
Key Facts:
- Calculated for temperatures ≥80°F and humidity ≥40%
- Full sunlight can increase perceived temperature by up to 14°F
- Children and at-risk groups (elderly, chronic illnesses) are more vulnerable
- Thirst indicates dehydration has already begun
Health Impacts:
| Heat Index | Risk Level | Effects |
|---|---|---|
| 80-90°F | Caution | Possible fatigue/cramps |
| 90-105°F | Extreme Caution | Heat exhaustion likely |
| 105-130°F | Danger | Heat stroke probable |
| 130°F+ | Extreme Danger | Medical emergency |
Important:
- Hydrate before feeling thirsty
- Reduce activity during peak heat
- Wear light, breathable clothing
- Never leave children/pets in vehicles
This version:
✓ Presents key information in scannable format
✓ Uses clear tables for danger levels
✓ Highlights actionable safety tips
✓ Removes technical assumptions about body types
✓ Focuses on practical implications
Would you like me to adjust the emphasis on any particular aspect?