Fuel Cost Calculator
Find what a journey costs in fuel. Enter the distance, your car's fuel consumption and the price per litre — get the total fuel used and its cost, plus the cost per person if you split it.
How to use this calculator
- Enter the trip distance in km and whether it's a round trip.
- Enter your car's consumption (L/100km) and the fuel price.
- Set the number of people to split the cost for a shared journey.
Formula used
Consumption in L/100km multiplies directly by the distance in hundreds of km. If you know mpg instead, convert first (or use the mileage calculator) — 235.2 ÷ mpg gives L/100km.
Example calculation
A 300 km trip at 7.5 L/100km and 1.75/litre: 300 ÷ 100 × 7.5 = 22.5 litres → 39.38.
Split between 3 people that's 13.13 each — often cheaper and greener than the train for a full car.
What a journey really costs
Fuel cost is one of the more decision-useful numbers a driver can have: it settles whether to drive or take the train, how much to charge for a lift-share, and how a longer but faster route compares to a shorter slow one. The maths is simple once consumption is in L/100km — distance and price do the rest.
The honest caveat is that official consumption figures are optimistic. Manufacturer test cycles run in ideal conditions, while real driving — cold engines, stop-start traffic, heavy loads, roof boxes, air conditioning and motorway speeds — pushes actual consumption 10–30% higher. Tracking your own litres-per-fill against distance gives a figure worth trusting, and this calculator with your real number beats any brochure claim.
Why use this calculator?
- Decide between driving, train or a shared ride on real cost.
- Split a road-trip's fuel fairly between passengers.
- Compare routes and driving styles by cost per km.
Frequently asked questions
How do I calculate the fuel cost of a trip?
Multiply distance (in hundreds of km) by your consumption in L/100km to get litres, then by the price per litre. A 300 km trip at 7.5 L/100km and 1.75/L costs 300/100 × 7.5 × 1.75 = 39.38.
Why is my real fuel cost higher than calculated?
Official consumption figures assume ideal conditions. City driving, cold starts, heavy loads, roof boxes, high speeds and air conditioning all raise real consumption by 10–30%. Use your own tracked L/100km for an accurate estimate.
Is it cheaper to drive or take the train?
For a solo traveller the train often wins; for a full car, fuel cost split several ways is usually cheaper per person. This calculator's per-person figure lets you compare directly against a ticket price.