Aviation unit converter
Distance, speed, altitude, weight, volume, fuel, pressure and temperature — the conversions that actually come up.
The ones that catch people
Fuel weight is not one number. Avgas is about 6.0 lb per US gallon, Jet A about 6.8. Both vary with temperature — colder fuel is denser, so a gallon weighs more — which matters for weight and balance at the margins.
Imperial and US gallons differ by about 20%. An imperial gallon is 4.55 litres against the US 3.79. Refuelling in a country that uses one while planning in the other is a genuine and recurring source of fuel exhaustion.
Altimeter settings come in two flavours. Inches of mercury in North America, hectopascals almost everywhere else. 29.92 inHg is 1013.25 hPa, and one inch is about 34 hPa.
Nautical and statute miles are not interchangeable. Visibility in a US METAR is statute; distances on charts and in flight planning are nautical. A nautical mile is 1.15 statute miles, which is enough to matter when the visibility minimum is 3.
Other calculators
- Density altitude calculator
- Pressure altitude calculator
- True airspeed calculator
- Crosswind component calculator
- Wind correction angle and groundspeed calculator
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- Top of descent calculator
- Climb gradient calculator
- Time, speed and distance calculator
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For planning and study, not for operational use. Aircraft performance comes from your POH, not from a generic formula.