Air Density and Density Altitude Calculator

Estimate pressure altitude, ISA temperature, dry-air density, density ratio and density altitude from elevation, QNH and OAT.

richie woods

A basic environmental planning calculator for understanding air-density effects on UAS performance.

Local calculation: values are processed in your browser and are not transmitted. Optional profiles are stored only in this browser.
Active profile: Manual values
ft AMSL
hPa
°C

Planning output only. Verify assumptions and results against authoritative data, manufacturer information, approved procedures, test evidence and competent engineering or regulatory review before use.

Calculation basis

Pressure altitude is estimated from site elevation and QNH. Standard-atmosphere pressure at that pressure altitude is combined with the entered dry-air temperature to estimate density. Density altitude is the ISA altitude with the same density.

Limitations and verification

  • Humidity is not included; high moisture content lowers density further.
  • Uses a standard-troposphere model and is intended for planning, not certified performance computation.
  • Use current official weather, manufacturer performance data and approved limits for operations.

Version and review status

Formula set: v1.2
Staging review date: 17 August 2026
Status: Staging beta pending user acceptance and cross-browser checks.