Air Properties Calculator

Psychrometric properties of moist air — humidity ratio, dew point, density and enthalpy.

Enter the air state

Dry Bulb Temperature, T (°C)

Relative Humidity, RH (%)

Atmospheric Pressure, P (kPa)

Sea level ≈ 101.325 kPa

Calculated psychrometric properties

Saturation Vapor Pressure

0.000 kPa

Actual Vapor Pressure

0.000 kPa

Humidity Ratio, W

0.00 g/kg dry air

Dew Point Temperature

0.00 °C

Moist Air Density

0.000 kg/m³

Specific Enthalpy

0.00 kJ/kg dry air

Psychrometric formulas (Magnus approximation, ideal-gas air/water vapor mixture)

Psat: 0.6108·exp(17.27T/(T+237.3)) kPa

Pv: Pv = RH·Psat

W: W = 0.622·Pv/(P−Pv)

Tdp: 237.3·ln(Pv/0.6108) / (17.27−ln(Pv/0.6108))

ρ: ideal-gas law, dry + vapor partial pressures

h: h = 1.006T + W(2501+1.86T)