Wet Bulb & WBGT Calculator
Enter the temperature and humidity to compute the wet-bulb temperature, wet-bulb globe temperature (WBGT), heat index, dew point and real feel: each graded by its danger level.
Wet bulb vs. WBGT: what’s the difference?
The wet-bulb temperature is the lowest temperature air can reach by evaporating water into it: a direct measure of how much cooling your sweat can still provide. Near 35 °C (95 °F) wet-bulb, a healthy person can no longer shed heat even at rest in the shade.
Wet-bulb globe temperature (WBGT)is the broader heat-stress standard: it blends the wet bulb with air temperature and, outdoors, the black-globe temperature that captures direct sun and wind. It’s what the military, athletic associations and occupational-safety bodies use to set activity limits.
How this calculator works
Wet bulb uses the Stull (2011) approximation; heat index uses the NWS Rothfusz regression; dew point uses Magnus-Tetens; real feel uses the Australian Bureau of Meteorology apparent-temperature formula. WBGT is shown two ways: a full-sun estimate (assuming clear, overhead midday sun) and the shadeform our live readings use (0.7 × natural wet bulb + 0.3 × air temp, with the natural wet bulb from the Liljegren model with no direct sun, so wind changes it); the exact in-sun figure needs solar radiation for your location and time. The colors match our published methodology.
Want the real, in-sun WBGT for where you actually are, plus a 7-day forecast and a personal “safe for me” read? Open WetBulbTracker, or read WBGT vs. heat index.