How to use this calculator
- Enter your own values in the labeled fields. Check the units and assumptions before comparing results. Only the fields needed for your selected calculation mode are shown.
- Your answer updates automatically. Review the calculation steps to see exactly how it was calculated.
- Copy, share, save, or download your result. Saved inputs stay on this device.
How the calculation works
Enter the total distance including any return journey. Match the economy and price units using the selected system. US and Imperial gallons differ, so a price per one gallon type cannot be combined with MPG based on the other. The result covers fuel only, not tolls, depreciation or parking.
A worked example
300 km at 7 L/100 km uses 21 L. At $1.50/L, the fuel costs $31.50, or $15.75 each for two people.
Reading your result
Use the main result together with its units and supporting figures. Display values are rounded; calculations keep their underlying precision. A change in inputs or assumptions can change the answer. Compare the step-by-step working with your intended use before relying on an estimate.
Frequently asked questions
Is the fuel price live?
No. Enter the price you want to model.
Does it add a return journey?
No. Enter the full distance yourself.
Sources & methodology
NIST: international unit conversion factors ↗
Formula review: October 24, 2026. Read our methodology.