Atsusaban WBGT Heat Index

Atsusaban estimates the WBGT heat index from temperature and humidity and shows the risk on a five-step scale. It works completely offline — every calculation runs on your device.

Check a gym, a worksite, a parked car or a room, and keep the reading as a record.

WHAT YOU CAN DO
- Enter temperature (10-45C) and humidity (0-100%) with sliders
- See the estimated heat index and a five-step risk level shown in colour
- Read the suggested action for each level
- Save readings with a place name
- View the day's readings on a time chart
- Browse and delete your records

ATSUSABAN PRO (one-time purchase)
- Unlimited saved records (free version keeps 30)
- Unlimited place presets (free version keeps 1)
- Copy your records as CSV
- No ads

PLEASE NOTE
The value shown is an estimate calculated from temperature and humidity only. No black-globe correction is applied, so readings in direct sunlight may come out lower than the official figure. Outdoors, please rely on the values published by Japan's Ministry of the Environment. This app is not a medical device and does not diagnose or assess your health. If you feel unwell, move somewhere cool and seek medical advice.