500 km at 7 L/100 km
500 × 7 ÷ 100 = 35 L
At a fuel price of 1.80 per liter, the estimated trip cost is 63.00. Shared between three people, the estimate is 21.00 each.
The cost per kilometer is 0.126, displayed as ≈ 0.13 at two decimal places.
Travel and everyday costs
Fuel Cost Calculator
Estimate fuel needed, trip cost, and a per-person share using your own fuel price.
Estimate the fuel cost of a trip
Estimated trip fuel cost
Enter your distance, consumption, and price, then select Calculate.
- Fuel needed · price unit
- Fuel needed · liters
- Cost per distance
- Per-person share estimate
Your inputs are processed in your browser and are not sent to a server. This estimate covers fuel only; parking, tolls, and other travel costs are excluded.
Fuel cost examples
300 miles at 30 US mpg
300 ÷ 30 = 10 US gal
At 3.50 per US gallon, the estimated cost is 35.00. The fuel volume is exactly 37.85411784 liters under the entered consumption assumption.
The example prices are illustrations, not current fuel prices.
240 km at 12 km/L
240 ÷ 12 = 20 L
At 1.50 per liter, the estimated cost is 30.00. Kilometers per liter describes distance covered by one liter, so distance is divided by this value.
For L/100 km, distance is multiplied by consumption and divided by 100.
Formulas and unit conversions
- L/100 km: fuel in liters = distance in km × consumption ÷ 100.
- km/L: fuel in liters = distance in km ÷ fuel economy.
- US mpg: fuel in US gallons = distance in miles ÷ US mpg.
- Imperial mpg: fuel in Imperial gallons = distance in miles ÷ Imperial mpg.
Fuel is converted to the unit of your price before the cost is calculated: trip cost = fuel quantity × price per unit. Cost per distance divides trip cost by the entered distance. For zero distance, fuel and trip cost are zero, and cost per distance is undefined. The share estimate divides the unrounded trip cost by the number of people.
The exact conversion constants are 1 mile = 1.609344 km, 1 US liquid gallon = 3.785411784 L, and 1 Imperial gallon = 4.54609 L. Sources: NIST mile conversion, NIST Handbook 44 (2026), Appendix C (US gallon, PDF), and NIST SI Guide, Appendix B.8 (Imperial gallon).
Calculations use 100 significant decimal digits internally. Display rounding happens only at the selected 2, 4, 6, or 10 decimal places; exact halfway values round away from zero. The ≈ symbol identifies display rounding. A result without that symbol still depends on your distance, consumption, and price assumptions.
Common questions
Can I mix miles, metric fuel economy, and a price per gallon?
Yes. Select the unit for each input independently. The calculator converts distance and fuel volume before pricing the fuel. Changing a unit does not convert the number already in its input, so check that number before calculating again.
Are US and Imperial mpg the same?
No. Both use miles, but an Imperial gallon contains more liters than a US liquid gallon. Using the wrong mpg or price unit changes the estimate. Match each unit to the source of the figure you enter.
Does the distance include the return journey?
Only if you include it in the distance you enter. For a round trip over the same route, add the outward and return distances. The calculator does not look up routes or add a return journey.
Why might actual fuel cost be different?
The estimate assumes a constant fuel consumption and price for the entered distance. It does not model changing driving conditions or different prices at each stop. It also excludes parking, tolls, maintenance, and other travel expenses.
Do the displayed shares add up exactly?
Not always. Each share is the unrounded trip cost divided by the group size, then rounded for display. For example, a cost of 1 shared between three people displays as approximately 0.33 each at two decimal places. This calculator does not distribute a remaining cent or prescribe payment amounts.
Which currencies and input values are supported?
Use any one currency, without entering its symbol. No currency conversion or currency-specific rounding is applied. Distance and price may be zero; consumption must be positive. Numeric inputs allow up to 15 digits before the decimal point and 10 after it, with a dot as the decimal separator and optional correctly grouped thousands commas. Expressions and scientific notation are rejected. Group size is a whole number from 1 to 1,000; blank means one person.