Density Altitude Calculator
Estimate pressure altitude and density altitude with the common pilot rule of thumb, and see every step. This estimate does not tell you whether your airplane can take off or climb. Only the POH/AFM performance charts do.
Estimated density altitude
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Substituted calculation
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The approximation and its range
- Pressure altitude ≈ elevation + (29.92 − altimeter) × 1,000 ft
- Standard (ISA) temperature ≈ 15 °C − 2 °C per 1,000 ft of pressure altitude
- Density altitude ≈ pressure altitude + 120 ft × (OAT − ISA temperature)
The 1,000 ft per inch and 120 ft per °C factors are rules of thumb taught in the FAA Pilot's Handbook of Aeronautical Knowledge. They're closest to exact values below roughly 10,000 ft and within normal temperature ranges, and they ignore humidity (humid air makes the true density altitude a bit higher). This calculator accepts elevations from −1,500 to 15,000 ft and temperatures from −60 to 55 °C.
For takeoff distance, climb rate and whether to go at all, use the performance charts for your exact airplane, plus a margin. A density-altitude number alone doesn't decide that.