Journey Fuel Cost Calculator
Working out a journey's fuel cost is easy; splitting it without losing a penny is where it goes wrong. Dividing a total by three and rounding each share gives an amount that does not add back to what was actually spent — and somebody is always a penny out. This works in whole pence and hands the remainder out one at a time, so the shares reconcile exactly.
What this generator does
Multiplies distance by consumption to get litres, multiplies by price to get the cost, then divides it between passengers in whole pence — giving the remainder out a penny at a time so nothing is lost.
How to use this tool
- Enter the distance, your car's consumption and the fuel price.
- Set how many people are splitting it.
- Read each share — they differ by at most a penny and add back exactly.
- The return figure is there because most journeys have one.
Understanding the controls
- Distance
- The journey in kilometres, between 10 and 2000.
- Litres per 100 km
- Your car's consumption. Real-world figures are usually worse than the official ones, particularly in town.
- Price per litre
- What you actually pay at the pump, including any discount — the figure on the sign is per litre, so no conversion is needed.
- Splitting between
- How many people share the cost. The shares differ by at most a penny and always add back to the total.
Common use cases
- Splitting fuel fairly on a shared journey
- Working out what a regular commute costs in fuel
- Comparing driving against other transport on cost
- Claiming or checking a mileage expense
- Understanding cost per kilometre for a vehicle
How this generator works
Everything happens in whole pence, which is the only way a split reconciles. The check confirms three separate things: the shares add exactly to the total, no two differ by more than a penny, and the per-kilometre figure multiplies back — with a tolerance sized for the rounding it is measuring through, since over 900 km half a ten-thousandth is more than four pence.
Randomness and fairness
Nothing here is random. The cost follows entirely from the distance, consumption and price you enter.
For how randomness is produced across the whole site, see how Generate Random works.
Limitations and good to know
- Fuel only. Wear, tyres, servicing, insurance and depreciation are all real costs of a journey and none appears on a forecourt receipt.
- Consumption is treated as constant, whereas it varies enormously with speed, load, terrain and traffic.
- Metric throughout — litres per 100 km and kilometres.
- Assumes an equal split. Splitting by distance travelled or by who drove is a different calculation.
Privacy and your data
The calculation runs in your browser. The figures you enter are never transmitted or stored.
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