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

## Pressure Altitude Formula

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

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

• Where h(alt) is the altitude pressure (ft)
• P is the measured pressure

## Pressure Altitude Definition

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

## Pressure Altitude Example

How to calculate altitude pressure

1. First, measure the station pressure.

This station pressure will normally be measured in mm or inches of mercury.

2. Next, convert to pressure.

Convert the pressure from mm or in of mercury to millibars.

3. 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.