Gas & Trip Cost Calculator
Before a road trip or a long commute, it helps to know what the fuel alone will cost. Set the one-way distance, your vehicle mileage, and the price of gas to see both the one-way and round-trip totals. The numbers move as you slide.
How this math works
Gallons used equals the trip distance divided by your vehicle miles per gallon. Multiplying those gallons by the price per gallon gives the one-way fuel cost, and doubling it gives the round trip.
Real mileage varies with speed, terrain, traffic, and weather, so treat the result as a close estimate. Highway driving usually beats the rated mileage while heavy city traffic falls short.
Common questions
Does this include tolls or wear on the car?
No. The tool covers fuel only. Tolls, parking, maintenance, and depreciation are real costs of driving but are not part of this estimate.
Why is my real mileage different from the rating?
Posted MPG is measured under controlled conditions. Your actual mileage shifts with driving speed, terrain, traffic, cargo, and weather.
How do I estimate cost for an electric vehicle?
This calculator is built for gasoline. For an electric vehicle you would compare cost per kilowatt-hour and efficiency in miles per kilowatt-hour instead.
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