Fuel Cost Calculator

Inputs and units

Enter distance in miles, fuel efficiency in miles per US gallon and price per US gallon.

Formula

Gallons = miles / MPG; cost = gallons × price per gallon.

Worked example

300 miles at 30 MPG and $3 per gallon costs $30.

Assumptions and limitations

Uses US gallons and constant fuel economy. Traffic, terrain, idling, weather, detours and changing prices can affect actual cost.

Understanding your result

Estimated fuel used is trip distance divided by miles per US gallon. Cost multiplies that fuel by your price per US gallon. Use a realistic average for your vehicle and route rather than the best mileage you have ever recorded.

A practical comparison

A 300-mile trip at 30 MPG uses 10 US gallons. At $3 per gallon the fuel budget is $30. If the same trip averages only 25 MPG, it uses 12 gallons and costs $36. Run both cases to see how sensitive your budget is to traffic or driving conditions.

Common mistakes

• Use the full round-trip distance if you are budgeting a return journey.
• US and Imperial gallons differ; match the fuel economy and price units.
• Fuel cost excludes tolls, parking, vehicle wear and accommodation.

Frequently asked questions