Enter the total number of in or mm of mercury (or milibars) into the calculator. The calculator will display the equivalent pressure altitude in ft or meters.

- Partial Pressure Calculator
- Compression Ratio Calculator
- Vapor Pressure Calculator
- Air Density Calculator

## Pressure Altitude Formula

The following formula is used to convert in of mercury into altitude feet.

h(alt) = ( 1 – ( P / 1013.25) ^ .190284) * 145366.45

- Where h(alt) is the altitude pressure (ft)
- P is the measure pressure

## Pressure Altitude Definition

Pressure altitude is defined as the relationship between the atmospheric pressure and the distance above the surface of the earth.

## Pressure Altitude Example

How to calculate altitude pressure

**First, measure the station pressure.**This station pressure will normally be measured in mm or in of mercury.

**Next, convert to pressure.**Convert the pressure from mm or in of mercury to millibars.

**Calculate the altitude pressure.**Using the pressure from step 2, calculate the pressure altitude using the formula above.

## FAQ

**What is pressure altitude?**

Pressure altitude is the equivalent height in the atmosphere one would travel in order to reach the pressure given.