About this tool
The Fuel Burn, Endurance & Range Calculator estimates how long you can fly and how far you can go on the fuel on board, after setting aside a reserve. Enter your usable fuel, hourly fuel burn, a reserve to keep untouched, and your ground speed. It returns endurance to reserve, endurance to dry tanks and range, all computed live in your browser.
Endurance to reserve is (usable fuel − reserve) ÷ burn rate, in hours. Range is that endurance × ground speed, in nautical miles. The tool also shows total endurance to dry tanks (fuel ÷ burn) for reference, but you should always plan to land with the reserve intact.
Use any consistent volume unit — US gallons with gallons per hour, or litres with litres per hour — since the units cancel in the endurance. Ground speed determines range, so account for wind: a headwind shortens your range for the same endurance, while a tailwind extends it.
Frequently asked questions
How is endurance calculated?
Usable endurance = (usable fuel − reserve) ÷ hourly burn. It is the flying time available before you would dip into your reserve. Total endurance to dry tanks is simply fuel ÷ burn, shown for reference only.
How is range worked out?
Range = usable endurance × ground speed. Because it uses ground speed rather than airspeed, it already accounts for wind if you enter the ground speed you expect to see on that leg.
What units should I enter?
Any consistent volume unit for fuel, burn and reserve — gallons with gallons/hour, or litres with litres/hour. The units cancel when dividing, so endurance is correct either way; range comes out in nautical miles from ground speed in knots.
Why keep a reserve?
Regulations and good practice require you to land with a minimum fuel reserve for diversions and unexpected delays. Setting a reserve here gives usable endurance to that point, not to fuel exhaustion. Always confirm with your aircraft's official fuel figures.
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