Calculate your result
Enter your figures below. Values stay in your browser.
How to use MPG Calculator
- Enter your figures in the units shown beside each field. Keep monetary inputs in the same currency; money results are currently displayed in USD.
- Select the unit standard where the form offers a choice, then choose Calculate.
- Read the breakdown and compare the worked example below. Change one assumption to see its effect.
Formula used
MPG = miles travelled ÷ gallons used, with the output labelled US or Imperial to match the input gallons.
Worked example
450 miles using 15 US gallons gives 30 US MPG. If the 15 gallons were Imperial gallons, the answer would instead be 30 Imperial MPG.
What the result means
Do not enter litres into the gallons field. Use consistent fill levels and combine several tanks for a more representative figure.
Check your result
Results retain calculation precision internally and round for display. Keep the input values with the result so you can reproduce it. Use Reset to restore the example inputs, or Copy result to copy the displayed answer.
If the result does not agree with your own calculation, report the page, inputs and expected answer. See our methodology and reference sources for the standards used.
Related tools
Fuel Cost Calculator
Use Fuel Cost Calculator when a dashboard, advert or workshop note gives you distance, fuel economy and the price at the pump in a different unit or format.
Fuel Consumption Calculator
Fuel Consumption Calculator turns distance travelled and fuel used into a result you can check against the figures from your car, route or workshop note.
KM/L Calculator
KM/L Calculator works well as a second check: enter kilometres travelled and litres consumed, then keep the original units beside the answer.
L/100km Calculator
With L/100km Calculator, the result is built from distance travelled and fuel used; change one input at a time when comparing scenarios.
Formula, worked example and limitations updated September 10, 2026.