Geography & Earth
Advanced

Barometric Formula

Atmospheric pressure as a function of altitude.

Formula

P=P0e−MghRTP = P_0 e^{-\frac{Mgh}{RT}}

Variables

P_0Sea-level pressure
MMolar mass of air
gGravity
hAltitude
RGas constant
TTemperature

Example

Air pressure roughly halves for every 5.5 km you climb in altitude.

Did You Know?

Air pressure roughly halves every 5.5 km of altitude — which is why airliner cabins must be pressurized.

pressurealtitudeatmosphere