Density Altitude Calculator

About this calculator

Density altitude is pressure altitude corrected for non-standard temperature — the altitude in the International Standard Atmosphere (ISA) at which the air would have the same density as the air you're actually flying in. It's found by taking pressure altitude and adjusting it upward roughly 120 feet for every degree Celsius the outside air temperature is above the ISA standard temperature for that altitude (and downward for colder-than-standard air), since ISA temperature itself drops about 2°C per 1,000 feet from a 15°C sea-level baseline.

Hot, humid, high-elevation days push density altitude well above field elevation, which thins the air enough to lengthen takeoff roll, reduce climb rate, and cut engine and propeller performance. Pilots, flight instructors, and dispatchers check density altitude before departure from high or hot airports to confirm runway length and payload are safe for the day's conditions.