⛽ Fuel Burn Calculator
Enter the leg distance, your groundspeed, the fuel-flow rate, and a reserve requirement to estimate trip fuel, reserve fuel, and their total.
🛩️ How Much Fuel?
What is a Fuel Burn Calculator?
It turns a leg's distance and speed into the fuel you'll actually need. From the distance and groundspeed it works out the flight time, multiplies by your fuel-flow rate for trip fuel, then adds a reserve based on the minutes you want in the tanks on arrival — and totals the two.
Use it to understand how distance, groundspeed and fuel flow drive fuel, and how much a reserve adds. Units follow your burn rate, gallons or litres per hour. The results are illustrative estimates, not a fuel plan: plan fuel from the aircraft's POH/AFM with approved planning tools, and carry at least the reserve your regulator requires.
❓ Frequently Asked Questions
How is fuel burn calculated?
The calculator divides the leg distance by your groundspeed to get the flight time in hours, then multiplies that by your fuel-flow rate to get trip fuel. Reserve fuel is the reserve minutes converted to hours times the same burn rate. Total fuel is trip plus reserve. Work in whatever units your burn rate uses — gallons per hour or litres per hour — and the answers come back in the same unit.
What fuel-flow rate should I use?
Use the cruise fuel flow from your aircraft's performance charts for the planned power setting, altitude, and mixture — it's usually given in gallons or litres per hour. Climb burns more and descent burns less, so for a quick estimate a slightly conservative cruise figure covers the difference. For precise planning, break the flight into climb, cruise, and descent segments.
How much reserve fuel should I plan?
Regulations set minimums. In the US, 14 CFR 91.151(a) requires an airplane under VFR to carry enough fuel to fly to the first point of intended landing and then, assuming normal cruising speed, at least 30 minutes more by day or 45 minutes at night; IFR rules ask for fuel to an alternate as well. Those are floors, not targets; experienced pilots carry more. Enter your required reserve in minutes and the tool adds that fuel on top of the trip fuel so you see the total in one figure.
Why plan fuel by groundspeed rather than airspeed?
Fuel burned depends on how long you're airborne, and time aloft depends on groundspeed — your speed over the ground after wind. A strong headwind slows your groundspeed, stretches the flight time, and burns more fuel than the still-air figure suggests. Use your planned groundspeed for each leg. These are illustrative estimates, not a fuel plan; plan fuel from your aircraft's POH/AFM with approved planning tools and carry the required reserves.
What does the total leave out?
Fuel for start, taxi and run-up is not in the trip figure, and neither is the extra burned in the climb above the cruise rate: add them from your POH. Unusable fuel, also listed in the POH, sits in the tanks but cannot reach the engine, so it never counts. The total here is fuel you need usable on board, on top of those.