Dew Point Calculator
Calculate the dew point temperature from air temperature and relative humidity using the Magnus formula. Shows comfort level in both °C and °F.
About the Dew Point Calculator
The dew point is the temperature at which air must be cooled (at constant pressure) for water vapor to condense into liquid water. It is a direct measure of atmospheric moisture—unlike relative humidity, which changes with temperature, the dew point stays constant as long as the moisture content doesn't change. For hot and humid conditions, our Heat Index Calculator shows how the combined effect of temperature and humidity affects perceived warmth.
Dew point is particularly useful for weather forecasting, HVAC design, and agricultural planning. A dew point above 65°F (18°C) starts to feel uncomfortably humid to most people. The Magnus formula used here provides accuracy within ±0.35°C for temperatures between -40°C and 60°C. For cold-weather comfort assessment, see our Wind Chill Calculator.
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For a related calculation, use Fuel Cost Calculator to calculate trip fuel cost from distance, MPG, and fuel price. Also shows CO₂ emissions. Alternatively, use Heat Index Calculator to calculate the heat index (feels-like temperature) using the NWS Rothfusz regression formula.