Use this tool to accurately calculate the vapor pressure deficit for your specific environment, aiding in better climate control for your plants.
VPD Calculator
How the VPD Calculator Works
The VPD (Vapor Pressure Deficit) calculator helps you understand the difference between the amount of humidity in the air and the amount of humidity the air can hold when it’s saturated. This difference is the driving force for water to evaporate from plant leaves. Understanding this can help you optimize plant growth by controlling your growing environment.
How to Use the Calculator
To use this VPD calculator, input the current temperature of your environment in degrees Celsius and the relative humidity percentage. Then, click the “Calculate” button, and the calculator will display the VPD in kilopascals (kPa).
How It Calculates the Results
The calculator first determines the Saturation Vapor Pressure (SVP) using the temperature provided. The formula for SVP is based on the temperature-dependent Tetens equation. It then calculates the Actual Vapor Pressure (AVP) by applying the relative humidity percentage to the SVP. Lastly, VPD is calculated by subtracting AVP from SVP, and the result is displayed in kPa.
Limitations of the Calculator
While the VPD calculator is useful for general estimates, it has some limitations. The accuracy can be affected by factors such as the accuracy of the input values, elevation above sea level, and the precision of the environmental measuring equipment. It is designed to provide an estimate of VPD for standard conditions and should be used as a guide rather than an absolute value.