Fuel Cost Calculator
Calculate the fuel cost of a journey from distance, fuel efficiency and price, in imperial (mpg) or metric (L/100km) units.
US gallon = 3.785 L. Imperial gallon = 4.546 L. Currency is not converted.
Convert mpg ↔ L/100km in the fuel efficiency converter · EV cost: Electricity cost.
How to use
Choose the exact efficiency convention from your vehicle display, enter a price in the shown fuel-volume unit and ISO currency, then plan one-way, round-trip and shared costs.
FAQ
How is the fuel cost calculated?
The calculator converts distance and efficiency to kilometers and L/100km internally, then converts fuel back to US gallons, Imperial gallons or liters for your selected price unit.
Are US and Imperial gallons the same?
No. A US gallon is 3.785 L and an Imperial gallon is 4.546 L, about 20% larger. US mpg and UK mpg therefore produce different numbers for the same vehicle.
What happens when I switch units or currency?
Unit switches convert the current distance, efficiency and volume-based price. Changing the ISO currency code never applies an exchange rate; enter a price in that currency.
Does round trip double the distance?
Yes — turn on Round trip to multiply the distance by 2 automatically.
Can I split the cost?
Enter the number of passengers to see the cost per person — handy for carpools and road trips.
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