Density Altitude Calculator
Field elevation, altimeter, and temperature → density altitude, pressure altitude, and how far you are from a standard day. Critical for takeoff and climb performance.
Standard (ISA) temperature at 5,000 ft is 5°C. High density altitude — expect reduced climb and takeoff performance.
What density altitude tells you
Density altitude is pressure altitude corrected for non-standard temperature — the altitude your aircraft "feels" it's at. High elevation, high temperature, or low pressure all raise it, which means longer takeoff rolls, weaker climb, and reduced propeller and engine performance. On a hot day at a high-elevation airport, your density altitude can be thousands of feet above the field elevation.
The formulas used
- Pressure altitude = field elevation + (29.92 − altimeter) × 1,000
- ISA temperature at that altitude = 15°C − 2°C per 1,000 ft
- Density altitude = pressure altitude + 120 × (OAT − ISA temperature)
These are the standard approximations used on the E6B and taught for the FAA checkride.
FAQ
Why is my density altitude higher than the field elevation?
Because the air is warmer or the pressure is lower than a standard day. Every degree above ISA adds roughly 120 ft of density altitude.