Fuel volume and weight calculator
Fuel is ordered by volume and loaded into a weight and balance sheet as a weight. Converting between them needs a density, and that density is not a constant.
Calculator
This is an educational and planning aid. Use current official weather, your aircraft flight manual, and the rules that apply to your flight before you act on any figure here. See the aviation disclaimer.
What the result means
The result is the weight of the volume you entered, at the density you entered. Both halves matter: a wrong density gives a confident looking weight that is simply wrong.
The same density is also shown per litre and per US gallon, so the figure can be checked against whichever convention your paperwork uses.
When this is useful
- Completing a weight and balance calculation, where fuel has to appear as a weight.
- Converting between a fuel order in litres and an uplift figure recorded in kilograms.
- Checking how much the fuel load contributes to being over maximum takeoff weight.
How it is calculated
Weight is volume multiplied by density. The calculator converts your volume and density into consistent units before multiplying, so any combination of litres, gallons, kilograms and pounds works.
No density is filled in for you. That is deliberate, because assuming one is how weight and balance errors are introduced.
weight = volume x density
Worked example
- Fuel volume
- 100 litres
- Fuel density
- 0.72 kg per litre
The fuel weighs 72 kg, which is about 159 lb.
Check: 100 litres at 0.72 kg per litre is 72 kg by direct multiplication. Converting the density the other way gives 6.01 lb per US gallon, which matches the familiar figure of about 6 lb per US gallon for aviation gasoline.
Limitations
- Density changes with temperature. Cold fuel is denser, so the same volume weighs more on a cold morning than on a hot afternoon. For precise work, use the density at the actual fuel temperature.
- Different fuels have different densities. Aviation gasoline sits near 0.72 kg per litre at 15 C and Jet A-1 near 0.80, but these are reference points, not values to assume.
- The figures quoted on this page are for context only. Use the density from the fuel supplier or your own measurement for anything that matters.
Common mistakes
- Assuming a density rather than looking it up. A 10 percent density error on a full load is a large weight error.
- Mixing imperial and US gallons. An imperial gallon is about 20 percent larger, and both are called a gallon.
- Using a density in pounds per US gallon while the unit selector is set to kilograms per litre. The calculator warns when the number looks physically implausible.
Sources
- Pilot's Handbook of Aeronautical Knowledge, weight and balance , US Federal Aviation Administration