Free online calculator
Fuel cost calculator
Estimate trip fuel cost.
Estimate trip fuel cost
Normalize common fuel efficiency units and calculate the trip cost.
How to use this calculator
- 1
Enter efficiency
Use L/100km, km/L, US MPG, or UK MPG.
- 2
Add fuel price
Choose price per litre or per gallon.
- 3
Enter distance
Type the trip distance in kilometres or miles.
- 4
Check trip cost
Review fuel volume and estimated total cost.
Formula
Normalize efficiency: convert the selected unit to L/100km.
Fuel needed: litres = L/100km x distance_km / 100
Total cost: cost = fuel volume x fuel price
When fuel is priced per gallon, the calculator converts litres to the matching gallon size before multiplying.
Worked example
Driving 100 miles at 30 MPG:
A 100-mile trip at 30 US MPG uses 100 / 30 = 3.33 gallons. At $3 per gallon, the fuel cost is about $10.
FAQ
How do you calculate fuel cost for a trip? +
Calculate fuel cost by estimating fuel needed for the distance, then multiplying that fuel volume by the fuel price. This calculator normalizes units before costing the trip.
How many litres of fuel do I need? +
Litres needed equals L/100km multiplied by trip kilometres divided by 100. A car using 6 L/100km needs 6 litres for 100 km.
Can I use MPG in this fuel cost calculator? +
Yes, you can use US MPG or UK MPG. The calculator converts MPG to L/100km internally before estimating fuel volume.
What is the difference between US and UK MPG? +
US MPG and UK MPG differ because a UK imperial gallon is larger than a US gallon. Select the version that matches your vehicle rating.
Does this include tolls or parking? +
No, this fuel cost calculator only estimates fuel spend. Add tolls, parking, and maintenance separately for a full trip budget.
About this calculator
This fuel cost calculator estimates how much petrol or gas a trip will use and what it will cost. Enter your vehicle efficiency, fuel price, and distance in the units you already know.
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