How does the Fuel Cost Calculator work?
The calculator multiplies the distance per trip by the number of trips, divides total miles by the MPG value you enter to estimate gallons required, and then multiplies gallons by the fuel price per U.S. gallon. 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 gallon for the fuel grade and locations you expect to use. 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
Gallons needed equals total miles divided by MPG, and fuel cost equals gallons needed multiplied by price per gallon.
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. The math works for any fuel priced per U.S. gallon when the vehicle efficiency is entered in matching miles per gallon.
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.