Fuel Cost Calculator

Estimate the fuel cost of a trip from distance, fuel efficiency, and gas price.

The math behind the estimate

For mpg, gallons needed = trip distance (miles) ÷ mpg. For L/100km, liters needed = (trip distance in km ÷ 100) × the L/100km rating. Either way, multiplying the fuel needed by the price per unit gives the total cost.

Why real trips often cost more

Highway driving is usually more efficient than city driving, and factors like AC use, cargo weight, and terrain all affect real-world fuel consumption compared to a vehicle's rated efficiency. Treat this as a planning estimate rather than an exact figure.

Don't know your vehicle's fuel efficiency? Use our Gas Mileage Calculator to measure it from your own fill-ups.

Common questions

Can I mix units, like distance in km with mpg?

Yes — distance, efficiency, and price units are each converted independently, so any combination works.

Does this account for round trips?

No — enter the one-way distance, or double it yourself if you want a round-trip estimate.

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