Calculate total fuel on board and usable fuel using tank quantities and unusable fuel. This free aviation calculator helps pilots verify available fuel for flight planning.
Enter the fuel quantity in each tank and any unusable fuel to calculate total fuel on board and usable fuel.
This calculator is a planning aid and does not replace approved fuel measurement procedures.
Fuel on board is the total amount of fuel currently in the aircraft tanks. Pilots often distinguish between total fuel on board and usable fuel, because not all fuel in the system may be approved or available for normal flight use.
Calculating fuel on board helps support fuel planning, endurance calculations, and preflight verification of available fuel.
Total fuel is all fuel physically in the tanks. Usable fuel is the portion approved and available for normal flight use.
Unusable fuel is not counted as available flight fuel, so it must be excluded when calculating usable fuel for planning.
Yes. If the aircraft does not have auxiliary tanks or they are not being used, leave that field blank and the calculator will treat it as zero.
No. This calculator is a planning aid. Pilots should always verify actual fuel quantity using approved aircraft procedures and real-world fuel checks.