Tools

Fuel Calculator

Work out how much fuel you need for a race in any sim – for timed or lap races, with a safety margin, pit stops when one tank isn't enough, and how much you'd need to save to make it without stopping. Racing Le Mans Ultimate with Virtual Energy? Use our Race Strategy tool instead.

Your race

I want to know
Race type
Units
Race lengthHours : minutes
5 min24 h
Race lapsLaps
1300
Lap timeAverage, m:ss.s
0:308:00
Fuel per lapLitres
Safety marginExtra laps of fuel
05 laps
Tank sizeLitres

Get your fuel per lap from a few clean laps in practice: note the fuel left, do 3–5 laps at race pace and divide what you used by the number of laps.

Fuel for your race

How the fuel calculator works

  • Timed races finish on the first time you cross the line after the clock runs out, so you always need fuel for one more lap than fits in the time. In multiclass races the flag falls for the overall leader, so use the leader's lap time if you're in a slower class.
  • Lap races are simple: laps × fuel per lap.
  • Safety margin covers a slower lap behind a safety car, a bit of extra wheelspin or a lap where you used more than usual. One lap is a good start; take more in a long race.
  • Formation lap: if your sim runs one, you use fuel on it before the race starts, so tick the box.

Pit stops and fuel saving

  • Plan pit stops splits the race into even stints, so you carry the same fuel each time and never more than the tank holds. Each stint keeps your safety margin in the tank, so you add the stint's fuel at each stop.
  • Fuel saving tells you the most fuel you can use per lap to finish on one tank (or the fuel you're allowed). Lifting and coasting before big braking zones is the easiest way to save without losing much time.
  • Check the sim's own fuel display in practice. Fuel use changes with the car, the track, the weather and how hard you push.

Frequently asked questions

How do I work out how much fuel I need for a race?

Multiply the number of race laps by your fuel per lap, then add a safety margin of at least one lap. For a timed race, divide the race length by your average lap time, round down and add one, because the race finishes on the lap after the clock runs out. Add one more lap of fuel if your sim runs a formation lap.

How many laps will a timed race be?

Divide the race length by your average lap time and round down, then add one. For example, a 60-minute race at 1:47.5 a lap is 33 full laps in the time, so you race 34 laps. In multiclass races the race ends when the overall leader crosses the line, so use the leader's lap time if you're in a slower class.

How do I find my fuel per lap?

Do a few clean laps at race pace in practice. Note the fuel at the start, drive 3 to 5 laps, then divide the fuel used by the number of laps. Most sims also show an average fuel per lap on the dash or in a fuel app, but check it over several laps.

How much safety margin should I take?

One extra lap is a good start for a sprint race. Take one to two laps for longer races, or if there could be safety cars or rain, because slower laps change how many laps you do and how much fuel you use.

How does the calculator plan pit stops?

Tick Plan pit stops and enter your tank size. The race is split into even stints so you never carry more than the tank holds, and each stint keeps your safety margin in the tank. At each stop you add the fuel for the next stint.

How much fuel do I need to save to finish without stopping?

Choose Fuel saving and enter the fuel you can carry. The calculator divides it by the race laps plus your margin to give the most fuel you can use per lap, and shows how much less that is than you use now. Saving a few percent is usually easy with a little lift and coast before the big braking zones.

Does it work for every sim?

Yes. It only uses your lap time and fuel per lap, so it works for ACC, iRacing, Automobilista 2, rFactor 2, RaceRoom, Assetto Corsa and any other sim. For Le Mans Ultimate cars with Virtual Energy, use the TSR Race Strategy tool, which plans energy and fuel together.

Can I use gallons?

Yes. Switch Units to Gallons and everything is shown in US gallons. The values you've entered are converted for you.

Is the fuel calculator free?

Yes, it's free for everyone. If you enjoy clean, friendly racing, join the Transatlantic Sim Racing community on Discord and take part in a championship.