Psychrometric Calculator

Interactive psychrometric chart for moist air in SI units. Click the chart or enter values to calculate all thermodynamic air properties. Includes two-point process analysis for HVAC load calculations.

Psychrometric Chart, SI Units
Click chart to set state point
Saturation (φ=100%)
Rel. Humidity φ
Wet Bulb Twb
Enthalpy h
State A
State B
m asl
Pa
°C
%
Air Properties
Dry Bulb Temperature-°C
Wet Bulb Temperature-°C
Dew Point-°C
Relative Humidity-%
Humidity Ratio-g/kg
Enthalpy-kJ/kgda
Specific Volume-m³/kgda
Density-kg/m³
Vapour Pressure-Pa
Saturation Pressure-Pa
kg/h
● State Point A (Initial)
°C
%
● State Point B (Final)
°C
%
Process Analysis
Enthalpy A-
Enthalpy B-
Δ Enthalpy-
Total Load-
Sensible Load-
Latent Load-
Hum. Ratio A-
Hum. Ratio B-
Moisture Change-