Online VPD Calculator | Optimize Plant Growth

5/5 - (1 vote)

Vapor Pressure Deficit (VPD) Calculator

Vapor Pressure Deficit (VPD) Calculation Result

Name Result
Temperature (°C):
Relative Humidity (%):
Disclaimer Don’t Rely On The Calculator, Do It Manually Too

VPD Calculator is a highly useful online tool that assists indoor gardeners in maintaining the ideal vapor pressure deficit (VPD) for their plants. 

Using a Vapor Pressure Deficit (VPD) calculator is a game-changer for indoor growers, as it tackles one of the most crucial aspects of plant health: vapor pressure deficit.

Basic Example To Use VPD Calculator

Certainly, here’s an example of how to use the Vapor Pressure Deficit (VPD) calculator:


Let’s say you are a farmer and you want to assess the VPD in your greenhouse to optimize the growing conditions for your plants. You measure the following parameters:

  1. Temperature inside the greenhouse: 25°C
  2. Relative Humidity inside the greenhouse: 60%

Using the VPD calculator, you input these values:

  • Temperature: 25°C
  • Relative Humidity: 60%

You click the “Calculate VPD” button, and the calculator provides you with the result:


Vapor Pressure Deficit (VPD): 1.27 kPa

Now, you know that the VPD in your greenhouse is 1.27 kilopascals, which helps you understand the drying power of the air. 

This information can be crucial in managing the environment for your plants, as different plant species have different VPD preferences for optimal growth and transpiration.

VPD Calculator Formula

The formula for calculating Vapor Pressure Deficit (VPD) in kilopascals (kPa) is as follows:



  • VPD is the Vapor Pressure Deficit in kilopascals (kPa).
  • es​ is the saturation vapor pressure (kPa) at the given temperature.
  • ea​ is the actual vapor pressure (kPa) in the air, calculated as the relative humidity (in decimal form) times the saturation vapor pressure.

What is the ideal VPD range for me?

The questions are very important about the ideal recommended VPD. The ideal range of VPD is around 0.8 – 1.2 kPa.

What is regarded as a high VPD?

The highly regarded VPD is beyond 1.3 kPa according to some growers.

If the VPD is too low, what are the consequences?

When the VPD is too low, it means that there is not enough vapor pressure difference between the plant leaf surface and the surrounding air.

This can result in reduced transpiration rates and increased humidity around the plants.

Final Thoughts

The VPD Calculator is a valuable online tool for growers to optimize their indoor growing environment. 

The above-given calculator is accurate and up-to-date use it according to your needs. Along with calculators, some examples are given that will help you to perfectly use it.