Term

pressure altitude

Daniel MarkFounder & Editor, Aviatopia
Published Mar 1, 2026Updated Mar 1, 20261 min read

The altitude indicated when the altimeter is set to the standard datum of 29.92 inHg (1013.25 hPa) — used for aircraft separation above transition altitude.

aviation-glossary

Quick Facts

Type
Altitude Reference
Definition
The altitude indicated when the altimeter is set to the standard datum of 29
Used By
Pilots

Definition#

Pressure altitude is the altitude shown on an altimeter when it is set to the standard barometric pressure of 29.92 inches of mercury (1013.25 hPa). It represents altitude in the standard atmosphere.

Why It Matters Operationally#

Above the transition altitude, all aircraft fly on standard pressure (pressure altitude, expressed as flight levels), ensuring consistent vertical separation regardless of local barometric variations.

See Also

Used in