Enter the temperature in Celsius into the calculator below to determine the water vapor pressure.

## Water Vapor Formula

The following formula is used to calculate the saturated water vapor pressure.

P = 0.61*e^{(18.68-T/234.5)*(T/(257.14+T)}

- Where P is the saturated vapor pressure (kPA)
- T is the temperature (C)

## Water Vapor Pressure Definition

A water vapor pressure is a pressure required in order for the water vapor in the air to be at equilibrium.

## Water Vapor Pressure Example

How to calculate water vapor pressure?

**First, measure the temperature of the air.**If necessary, convert the temperature into units of Celsius.

**Next, enter the temperature into the formula.**Calculate the water vapor pressure using the temperature from step 1 and the formula above.

**Finally, analyze the results.**Do the results make logical sense? If so, you have your answer, if not, check the calculation.

## FAQ

**What is water vapor pressure?**

A water vapor pressure is a specific pressure or maximum pressure required at any given temperature for the water vapor in the air to be at equilibrium.

**What is the formula for what vapor pressure?**

The following formula is used to calculate the water vapor pressure.