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Density altitude calculator

Barometric skydiving altimeters compute pressure and convert this to an indicated altitude. Density altitude, which takes into account temperature and humidity as well, is not measured although it is critical for flight performance. Use this tool to compute current density altitude at your location. You can fetch current weather conditions at your airport by entering its airport code, or set the conditions yourself. Those unfamiliar with these concepts can see our article Altitude types: pressure, indicated, true, density.

Default: Skydive City, FL (KZPH). Enter your dropzone’s nearest airport code for current conditions.
Density altitude—air performs as if the field were here in the standard atmosphere
Station pressure
Water-vapor pressure (e)
Actual air density (ρ)
Relative humidity

How it works. The tool runs the full three-step density form—dewpoint to water-vapor pressure, two-gas density, then a standard-atmosphere lookup—not the virtual-temperature shortcut many apps use. Current weather is the latest METAR observation from NOAA’s Aviation Weather Center, shown raw above so you can check it yourself. It is an observation, never a forecast. The formulas, and where every constant in them comes from, are derived in our altitude types article.

This tool is educational. Weather observations age, conditions change between any observation and any jump, and no number here accounts for wind, turbulence, or traffic. Nothing on this page is a substitute for proper training by certified instructors or for your own judgment at the dropzone. See, for example, the United States Parachute Association's Integrated Student Program, described in the Skydiver's Information Manual.