Dew Point Calculator

The Dew Point Calculator is a psychrometric tool used to determine the dew point temperature of air given its dry bulb temperature and relative humidity. The dew point is the temperature at which air becomes saturated with water vapor (100% relative humidity) and condensation begins to form. This calculation is vital in HVAC for understanding moisture content in the air, predicting condensation risk, and designing dehumidification systems. This calculator typically uses an approximation of the Magnus formula for its calculations.

Dew Point & Condensation: Understanding dew point is critical in HVAC. If a surface's temperature drops below the dew point of the surrounding air, condensation will form on that surface. This is why cold ductwork or windows might "sweat" in humid conditions. Air conditioners work by cooling air below its dew point, causing water vapor to condense on the evaporator coil, thus dehumidifying the air. High dew points (e.g., >65°F or 18°C) often indicate muggy and uncomfortable conditions, regardless of the dry bulb temperature.