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Aviation calculators/Altitude calculations/Density altitude
ALTITUDE CALCULATIONS

Density altitude calculator

Estimate how pressure and temperature combine to affect the air your aircraft flies in.

Instant resultsPressure altitude shown as a stepNo account needed

Airfield & weather

Live calculation

Use the published airfield elevation, current QNH, and outside air temperature at the airfield.

ft MSL
−1,500 to 20,000 ft
hPa
Sea-level altimeter setting
°C
Temperature at the airfield
Pressure units

Density altitude

LIVE RESULT
Temperature-adjusted estimate8,008 ft

Air density expressed as a standard-atmosphere altitude

Pressure altitude 5,500 ftISA temperature at pressure altitude 4.1 °COAT versus ISA +20.9 °C
THREE ALTIMETER REFERENCES

QNH, QNE & QFE at a glance.

QNH is referenced to mean sea level, QFE to the airfield, and QNE is the standard altimeter setting.

How it works
AIRFIELD5,500 ft MSLQNH · SEA LEVEL1013.25 hPaOCEAN · MEAN SEA LEVELQNE · STANDARD SETTING1013.25 hPaQFE · AT AIRFIELD827.42 hPaAltimeter reads ≈ 0 ft here

Swipe diagram to see all three settings →

Illustrative terrain; vertical distances are not to scale. QNE is a standard altimeter setting, not a physical pressure layer. QFE is estimated from QNH and elevation.
QNH1013.25 hPa

Reads 5,500 ft MSL at the airfield.

QNE1013.25 hPa

Reads 5,500 ft pressure altitude at the airfield.

QFE827.42 hPa

Reads approximately 0 ft at the airfield reference datum.

THE METHOD

From pressure to density.

We first calculate pressure altitude from airfield elevation and QNH. Then we compare outside air temperature with standard ISA temperature at that pressure altitude. Warmer-than-standard air raises density altitude; colder-than-standard air lowers it.

Planning approximationDensity altitude ≈ pressure altitude + 120 × (OAT − ISA temperature) ft

This is a simplified dry-air estimate. It does not account for humidity and should not replace aircraft-specific performance data.

UNDERSTAND THE INPUT

Start with pressure altitude.

The pressure altitude calculator focuses on the standard altimeter setting and explains QNH, QNE and QFE in the reference diagram.

Open pressure altitude calculator →

Reference: FAA density altitude approximation

A planning aid. Use approved performance data.

Density altitude is approximate. Check current weather and calculate takeoff, climb and landing performance with your aircraft’s approved handbook.