Trip Fuel Cost Calculator
What a journey costs in fuel, split between passengers, with the return trip included.
Fuel used is distance times consumption; cost is that times the price.
How the trip fuel cost calculator works
Fuel used is distance times consumption; cost is that times the price. The only complication is which consumption figure you use, and it is a large one — manufacturer figures are laboratory results and real driving is commonly 10 to 25% worse.
The reliable method is your own: fill the tank, drive normally, fill it again, and divide the liters by the kilometers. That number already includes your driving, your load and your routes.
Splitting between passengers is where a car beats most alternatives. A trip that costs more than a train ticket for one person is often a third of it for four.
Formula: litres = distance × L/100km ÷ 100; cost = litres × price
Worked examples
| Inputs | Fuel cost | Note |
|---|---|---|
| 420 km each way at 7.4 L/100km | $121.21 | 62.16 liters |
| Split four ways | $121.21 | a quarter each |
| In miles and US mpg | $55.25 | 16.25 gallons |
FAQFrequently asked questions
How do I work out the fuel cost of a trip?
Distance times consumption gives the fuel; multiply by the price. This page handles both metric and mpg.
Why is my real consumption worse than the brochure?
Manufacturer figures come from a standardized laboratory cycle. Real driving is commonly 10 to 25% worse, and more in cold weather or heavy traffic.
How do I measure my own consumption?
Fill the tank, note the odometer, drive normally, fill again. Liters divided by kilometers times 100 gives L/100km.
Is driving cheaper than the train?
For one person, often not. For three or four sharing, usually yes — the fuel cost splits and the ticket price does not.
Does air conditioning matter?
A few percent on the open road, more in stop-start traffic. Roof boxes and low tyre pressure cost considerably more.
Where these figures come from
- ISO 4000 / ETRTO — tyre designation and dimensions — the width / aspect ratio / rim marking this page decodes
- US Environmental Protection Agency — fueleconomy.gov — the official US fuel economy database
Last checked: September 2026. Tyre dimensions follow the ISO metric marking standard; engine formulas are the standard textbook forms.