How does the Fuel Cost Calculator work?
The calculator multiplies the distance per trip by the number of trips and divides total miles by the MPG value you enter. It can then show fuel needed in U.S. gallons or liters and multiplies that selected fuel quantity by the matching price per gallon or price per liter. It also shows the estimated fuel cost per mile.
Because gasoline prices and real-world MPG change, this is a scenario calculator rather than a live-price service. Enter the price available to you and an MPG value that fits your vehicle and expected driving conditions.
Which MPG number should you use?
For a future trip, you can use a recent personal MPG average, the vehicle’s trip-computer estimate or an official label value as a starting point. City-heavy driving, towing, winter weather, higher speeds and idling can reduce real-world fuel economy compared with an idealized assumption.
If you want to calculate MPG from fuel you already used, first use the Gas Mileage Calculator. Then return here with that measured MPG to estimate the cost of a planned route.
How should you choose a fuel price?
Enter a realistic price per U.S. gallon or per liter for the fuel grade and locations you expect to use, matching the unit selected in the calculator. A long road trip may cross areas with very different prices, so one average price is only an estimate. For a more detailed plan, split the route into segments with different prices and add the results.
The calculator covers fuel only. Tolls, parking, lodging, meals and other road-trip expenses belong in the Road Trip Cost Calculator.
What does the fuel-cost estimate leave out?
Fuel cost is only one part of operating a vehicle. Insurance, maintenance, tires, registration, financing and depreciation are not included. For an all-in annual perspective, use the Vehicle Ownership Cost Calculator or Cost Per Mile Calculator.
Frequently asked questions about Fuel Cost
With gallons selected, gallons needed equals total miles divided by MPG and cost equals gallons multiplied by price per gallon. With liters selected, the gallons result is converted to liters and multiplied by price per liter.
Yes. Enter 2 in the number-of-trips field when the return distance is the same as the outbound distance.
No. Enter the fuel price you expect to pay so the result reflects your own scenario.
Use the MPG estimate that best matches the route. Mixed driving may be better represented by your recent real-world average.
Enter one-way or round-trip distance consistently and set the number of trips to the number of repeated drives you want to estimate.
No. It estimates fuel only. Use the Road Trip Cost Calculator when you want to include other trip expenses.
Actual MPG, route changes, idling, detours and fuel prices can differ from the values entered.
Yes. Select Liters (L) and enter the price per liter. The MPG input remains U.S. miles per gallon; the calculator converts the required fuel quantity to liters before multiplying by your per-liter price.
Sources and methodology
The calculator uses the formulas described on this page and user-entered assumptions. These authoritative U.S. resources provide context for the related vehicle, fuel, charging, finance or safety topic.