Psychrometric Calculator
Interactive ASHRAE psychrometric chart - click two points to calculate process
Input
Chart Options
Click on the chart to set Point 1 (green)
Based on ASHRAE Fundamentals 2021 psychrometric equations
About This Calculator
This psychrometric calculator uses ASHRAE Fundamentals 2021 equations for saturation pressure and humidity calculations. All calculations support altitude correction.
Input Options: Calculate from dry-bulb plus relative humidity, wet-bulb, dew point, or humidity ratio.
Chart Interaction: Click anywhere on the chart to calculate the psychrometric state at that point. Use the Plot button to save points for comparison.
Altitude Correction: Enter your elevation in feet. The calculator adjusts barometric pressure using the standard atmosphere model.