Term

AGL

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

Above Ground Level — altitude measured from the terrain directly below the aircraft, as opposed to above mean sea level (MSL).

aviation-glossary

Quick Facts

Type
Altitude Reference
Also Known As
AGL
Used By
Pilots

Definition#

AGL stands for Above Ground Level. It measures altitude relative to the terrain directly beneath the aircraft. AGL heights change as the terrain elevation changes.

Why It Matters Operationally#

AGL is used for traffic pattern altitudes, minimum safe altitudes, obstacle clearance, and VFR cloud clearance requirements. Decision heights on precision approaches are expressed in AGL.

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