✈️ Density Altitude Calculator

Calculate density altitude from pressure altitude and temperature. Essential for aircraft performance calculations — takeoff roll, climb rate, and engine power.

Airport elevation

Elevation unit

Altimeter setting / QNH

Pressure unit

Outside air temp (OAT)

Temp unit

Performance Impact Reference

Density altitude	Typical impact	Action
< 2,000 ft	Near sea-level performance. Normal operations.	Standard procedures
2,000–5,000 ft	Slightly increased takeoff roll and reduced climb. Noticeable in hot/humid conditions.	Check POH performance charts
5,000–8,000 ft	Significant performance reduction. Longer runway required. Reduced max weight.	Consult POH; consider weight reduction
8,000–10,000 ft	Major performance degradation. Engine output down 25%+. Risk of runway overrun.	Early morning departure; max weight reduction
> 10,000 ft	Critical conditions for many light aircraft. Some aircraft cannot safely depart.	Verify aircraft ceiling; consider go/no-go carefully

🌡️ ISA temperature: The International Standard Atmosphere assumes 15°C at sea level, decreasing by 2°C per 1,000ft. If OAT is above ISA (hot day), density altitude is higher than pressure altitude. On a cold day it can be lower.

⚠️ High, Hot, and Heavy: The three H's are the pilot's warning for dangerous density altitude conditions. High elevation + high temperature + full fuel/payload = long takeoff roll and poor climb. Always calculate before departing from mountain airports in summer.

🛩️ Rule of thumb: For every 1,000ft of density altitude above sea level, expect approximately 3–3.5% reduction in engine power and a corresponding increase in takeoff distance. At 8,000ft DA, you may need 25–30% more runway.