Online Psychrometric Chart

This Online Psychrometric Chart is free to use. We hope it proves helpful to you.

Psychrometrics

Psychrometrics uses thermodynamic properties to analyze conditions and processes involving moist air.

Atmospheric air contains various gaseous components, including water vapor and some contaminants. Dry air is atmospheric air from which all water vapor and contaminants have been removed. Its composition is relatively constant, but small variations in the amounts of individual components occur over time, geographic location, and altitude.

Moist air is a binary mixture of dry air and water vapor. The amount of water vapor varies from zero (dry air) to a maximum, depending on temperature and pressure. Saturation is a state of neutral equilibrium between moist air and the water's condensation phase.

The psychrometric chart

A psychrometric chart graphically represents the thermodynamic properties of moist air. The choice of coordinates for a psychrometric chart is arbitrary.