Fuel Cost Calculator
Estimate fuel and total cost for a trip, commute or budget. Supports US and Imperial MPG, km/L, L/100 km, litres, gallons and international currencies.
Full Fuel Cost GuideTransparent methodology
How the fuel estimate is calculated
1. Complete the distance
Round trip doubles a one-way distance. Identical trips multiply the complete journey. Commute mode then applies the entered weekly schedule.
2. Standardize consumption
The engine converts US MPG, Imperial MPG, km/L or L/100 km into litres per 100 kilometres without mixing gallon definitions.
3. Apply the pump price
Fuel required is multiplied by the entered price per litre, US gallon or Imperial gallon after volume conversion.
4. Build the budget
Optional tolls, parking, other charges and fuel reserve remain visible. Passenger share divides the completed estimate equally.
Worked example
A 300-mile journey at 30 MPG (US) uses 10 US gallons. At USD 3.60 per US gallon, fuel costs USD 36.00, or USD 0.12 per mile. With 2 equal contributors, each share is USD 18.00.
Answers before you travel
Frequently asked questions
How do I calculate fuel cost for a trip?
Divide distance by fuel economy when using MPG or km/L, then multiply fuel required by the matching pump price. With L/100 km, multiply distance by consumption and divide by 100 before applying the price.
What is the difference between US and Imperial MPG?
They use different gallons. One Imperial gallon is larger than one US liquid gallon, so select the MPG form used by your vehicle or source.
How do I calculate a return journey?
Enter the one-way distance and select Round trip. The calculator doubles the distance before calculating fuel, charges and passenger share.
Can I calculate monthly commuting fuel cost?
Yes. Choose Commute, enter one-way distance, commute days per week and weeks per year. The average monthly result is annual cost divided by 12.
Can I split gas or petrol cost between passengers?
Yes. In Advanced options, enter everyone sharing the expense, including the driver when the total should be divided equally.
Does this calculator use live fuel prices?
No. Enter a current local price. Fuel prices change by place, grade and time, so a manually verified value is more transparent than an unexplained default.
Why might actual fuel use be different?
Traffic, speed, idling, weather, terrain, load, tyres, driving style and vehicle condition can all change consumption. Use a recent real-world average when possible.
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