Density Altitude Calculator
Type any airport and get density altitude instantly from live weather — plus pressure altitude and ISA deviation, the moment you land on the page.
Educational only — always fly your POH & current weatherCalculate density altitude
Drag the chart to set temperature — density altitude climbs ~120 ft per °C above standard.
Educational estimates only — not for flight planning, dispatch, or weight-and-balance.
What's the density altitude right now?
Tap Use my location and the calculator pulls the nearest METAR within 25 nm — altimeter setting and temperature — plus your elevation. Or type any airport ICAO code; the density altitude updates instantly, along with pressure altitude and ISA deviation.
Where is it highest right now? The Hot & High board ranks live density altitude at 300+ US mountain and desert airports. Run an airport, FBO or flight school? Put a free live density altitude badge on your website.
How density altitude works
Density altitude is pressure altitude corrected for nonstandard temperature — the altitude in the standard atmosphere where the air density matches what your aircraft is actually flying in. It's the altitude your aircraft thinks it's at. On a hot day at a high-elevation field, thin air robs lift, propeller thrust, and engine power — even though your altimeter still reads field elevation — which is why aircraft climb and accelerate so poorly when it's high and hot.
PA ≈ field elevation + (29.92 − altimeter) × 1000DA = PA + 120 × (OAT − ISA temp)Worked example — 5,000 ft field, 30 °C, 29.92"
The altimeter is standard, so pressure altitude = the 5,000 ft field elevation. ISA temperature at 5,000 ft ≈ 15 − 2×5 = 5 °C, so 30 °C is 25 °C warmer than standard (ISA+25). Density altitude = 5,000 + 120 × 25 = 8,000 ft — your aircraft performs as if it were most of the way to 8,000 ft while parked at a 5,000 ft field. The calculator above shows ≈7,988 ft using the exact ISA lapse rate.
The calculator assumes dry air. Humid air is slightly less dense, which can add a few hundred feet of density altitude on a hot, humid day, and the FAA's Density Altitude pamphlet (FAA-P-8740-2) advises adding 10 percent to your computed takeoff distance and expecting a reduced climb rate when humidity is high. Read the full guide: What is density altitude?
More free altitude tools
DensityAlt is a set of free, no-signup aviation calculators. Explore the rest:
Frequently asked questions
What is density altitude?
Density altitude is pressure altitude corrected for non-standard temperature — the altitude at which the air density you're flying in would occur in the standard atmosphere. On a hot day at a high field, density altitude can be thousands of feet above your actual elevation, which is why aircraft climb and accelerate so poorly in those conditions.
How do you calculate density altitude?
First find pressure altitude: PA = field elevation + (29.92 − altimeter setting) × 1000. Then correct for temperature: DA = PA + 120 × (OAT − ISA temperature), where ISA temperature is 15 °C minus about 2 °C per 1,000 ft of pressure altitude. The calculator above does this for you.
What's the density altitude right now at my location?
Tap Use my location above. The calculator pulls the nearest METAR (altimeter setting and temperature) within 25 nm, combines it with your elevation, and shows density altitude, pressure altitude and ISA deviation. If there's no METAR nearby, it falls back to a weather-model estimate (typically within ±200 ft, more at very high fields) and tells you so.
What counts as a high density altitude?
Any density altitude well above field elevation matters. As a rule of thumb, a normally-aspirated light single needs roughly 10% more takeoff distance for every 1,000 ft of density altitude and loses about 3% of its power per 1,000 ft. Above roughly 5,000–8,000 ft, many light singles become noticeably sluggish. These are rough estimates — always use your POH performance charts.
What's the difference between density altitude and pressure altitude?
Pressure altitude is your altitude in the standard atmosphere for the current pressure: PA = elevation + (29.92 − altimeter) × 1000. Density altitude corrects that for non-standard temperature: DA ≈ PA + 120 × (OAT − ISA temperature). Pressure altitude is what you enter performance charts with; density altitude is how the air actually performs. See the pressure altitude calculator.
How do I find the density altitude at an airport?
Type the airport's ICAO code (for example KDEN or KASE) and tap Look up. The live METAR autofills elevation, temperature and altimeter setting, and the density altitude is computed instantly. Fields without a METAR use the nearest reporting station within 25 nm.
How does density altitude affect takeoff?
Thinner air means less engine power, less propeller thrust and less wing lift at a given indicated airspeed. The result is a longer ground roll, a higher true airspeed at liftoff and a reduced climb rate. The takeoff and landing distance calculator gives a Koch-chart style estimate of the effect.
Found a bug or have an idea?
Spotted a wrong number, an airport that won't look up, or a calculator you'd love to see? Tell me — it shapes what gets built next.
About
Built by Levan Sulakvelidze — an instrument-rated private pilot based at KMYF (San Diego) and trained at KGAI (Gaithersburg, Maryland). DensityAlt grew out of genuine curiosity about how the air, your blood oxygen, and your airplane's performance all thin out with altitude — and a wish for free tools that get the physics right.