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⛽Trip Gas Cost Calculator
Formula
- Gallons = miles ÷ MPG
- Fuel cost = gallons × price per gallon
- Cost per mile = price per gallon ÷ MPG
Example: 300 miles at 28 MPG uses 10.7 gallons; at $3.25 a gallon that is about $34.82 one way.
Frequently asked questions
How do I find my car's MPG?
Check fueleconomy.gov for your model's EPA rating, or fill the tank, reset the trip meter, drive, refill and divide miles driven by gallons added.
Highway or city MPG?
Use the highway figure for long road trips and the combined figure for mixed driving. Heavy loads, roof boxes, speed above 65 mph and air-conditioning lower real-world MPG.
Where can I check current gas prices?
The U.S. Energy Information Administration publishes weekly average retail gasoline prices by region; apps and websites show local station prices.
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Last reviewed: 2026-10-17