Fuel Cost Calculator
Calculate fuel quantity and trip cost using your own distance, fuel economy and price. Select a matching unit system before entering numbers. This page has no live fuel prices, routes or tolls; costs use one entered currency without exchange rates. US mpg means US liquid gallons, which differ from Imperial gallons.
Calculation result
US gallons = miles ÷ US mpg. Liters = kilometers × L/100 km ÷ 100, or kilometers ÷ km/L. Cost = fuel × entered price per fuel unit.
Primary source: NIST SP 811 length and US liquid volume definitions. NIST SP 811 conversion factors supplies the unit definitions.
Worked example: 300 miles ÷ 30 US mpg = 10 US gallons; at 4 USD/US gallon the trip costs 40 USD. A 250 km trip at 8 L/100 km uses 20 L; at 1.5 EUR/L it costs 30 EUR.
How to use this tool
Choose miles with US mpg, kilometers with L/100 km, or kilometers with km/L. Enter a positive economy value, nonnegative distance and price, and a three-letter currency label. Switching modes changes labels and interprets the values in the new units; replace them as needed.
Frequently asked questions
Can I use kilometers and liters?
Yes. Choose L/100 km for consumption or km/L for economy. In both modes fuel price must be per liter.
Does this include live prices or tolls?
No. Distance, economy and fuel price are entered values. The result is fuel arithmetic only; it does not include tolls or other trip costs.
Is this calculator free and private?
Yes. Arithmetic runs on your device. Your entries are not uploaded or saved to browser storage, and no sign-up is needed.