Trip Cost Calculator
The Trip Cost Calculator computes trip cost from the relation cost = distance / fuel economy x price per gallon. It takes 3 inputs (trip distance in miles, vehicle fuel economy in mpg, fuel price in USD per gallon) and returns the trip cost. Because this is a pure mathematical or physical formula rather than a jurisdiction-specific rule, the result never changes over time: the same inputs always produce the same answer, so you can rely on it whether you are checking homework, sizing a design, or sanity-checking another tool. Enter your values in the fields below and the result updates instantly; you can also share a permalink that pre-fills the exact calculation, which is useful for teaching, reports, or collaboration. For example, with trip distance = 500 miles, vehicle fuel economy = 25 mpg, fuel price = 4 USD per gallon, the trip cost works out to 80, and the worked example further down the page shows every step so you can follow the arithmetic and reproduce it by hand. The method is the standard form documented by US DOE fueleconomy.gov, and the figure above each result carries the date it was last verified. This tool is general information and is not a substitute for professional engineering, medical, financial, or scientific advice; always check critical results against the primary source and your own judgement.
With Trip distance = 500 miles, Vehicle fuel economy = 25 mpg, Fuel price = 4 USD per gallon, the result is 80.
Applies to: any numeric inputs. Method source: US DOE fueleconomy.gov, checked 2026-06-23.
The formula
cost = distance / fuel economy x price per gallon
Worked example
With Trip distance = 500 miles, Vehicle fuel economy = 25 mpg, Fuel price = 4 USD per gallon:
- gallons needed = distance / mpg = 20.000
- cost = gallons x price = 80.00
- Trip Cost = 80
This worked example is one of the automated golden-value tests this calculator must pass before it can publish.
What this assumes
- Inputs are real numbers in the units shown.
- The result is the exact value of cost = distance / fuel economy x price per gallon; general information, not professional advice.
Frequently asked questions
What formula does this use?
cost = distance / fuel economy x price per gallon, the standard form documented by US DOE fueleconomy.gov.
Does the result ever change over time?
No. This is a pure formula with no external rate, so the same inputs always give the same result.
Official sources and verification
- Method: US DOE fueleconomy.gov, checked 2026-06-23.
Reviewed by the CalculatorHub team, edited by James Graham, 2026-06-23. See our methodology. General information, not professional advice.