Fuel Burn Calculator

About this calculator

Fuel burn planning starts with a fuel flow or burn rate — the gallons or pounds an engine consumes per hour at a given power setting — multiplied by planned flight time to get fuel required for the leg itself, then adds a reserve margin on top. The FAA requires VFR flights to carry at least 30 minutes of reserve fuel by day (45 minutes at night), while IFR flights must plan for 45 minutes of reserve at normal cruise, so reserve fuel isn’t optional padding but a regulatory minimum baked into every flight plan.

Pilots, flight instructors, and dispatchers calculate fuel burn during preflight planning to confirm an aircraft can complete a route with legal reserves intact, especially before cross-country flights, and to decide whether a fuel stop is needed. Owners of small aircraft also use burn-rate figures to compare the real-world efficiency of different cruise power settings against published performance charts.

This calculator takes your burn rate, flight time, and reserve requirement and returns the total fuel needed for the leg, including the reserve.