Trip Fuel Cost Calculator — Litres, Total & Per Person
Estimate fuel cost for any trip: distance, fuel economy (km/L or L/100km), price per litre, round-trip and cost split per person — instant results in your browser.
🔒 Runs entirely in your browser. Your input and output are never sent to a server or stored — fully private.
Total = distance (×2 if round trip) ÷ economy × price. Enter the price in your own currency — the result uses the same unit. Click any value to copy.
About this tool
How much will that drive actually cost? Enter the distance, your car's fuel economy in km/L or L/100km, and the pump price per litre, and this calculator returns the litres needed and the total fuel cost — with a round-trip toggle that doubles the distance and a splitter that divides the bill fairly among passengers. Use it to budget a road trip, settle up after sharing a drive, or check whether taking the car beats the train. The maths runs entirely in your browser, so the routes and prices you enter never leave your device.
Frequently asked questions
What is the difference between km/L and L/100km, and how do I convert between them?
They describe the same efficiency from opposite directions. km/L states how far one litre takes you — bigger is better — and is the everyday unit in Japan and much of Asia. L/100km states how much fuel 100 km consumes — smaller is better — and is standard in Europe. Converting is simple: divide 100 by the value, so 12.5 km/L equals 8 L/100km and vice versa. This tool accepts either unit directly, so you can type whichever figure your car or country uses.
Why does my real trip usually cost more than the calculated figure?
Official fuel-economy ratings are measured in laboratory cycles, and real-world driving is usually 10–30% thirstier: city traffic, cold starts, air conditioning, roof boxes, headwinds, hills and a full load of passengers all eat into the rated figure. For a realistic estimate, use the average your trip computer shows over recent months, or fill the tank, drive normally, refill and divide kilometres by litres. And remember this tool covers fuel only — tolls, parking and wear are on top.
How do round trip and cost splitting work, and is my data stored?
The round-trip option simply doubles the one-way distance before working out litres and cost, and the splitter divides the total evenly by the number of people you set — whether the driver chips in is up to your group, so adjust the headcount to match your agreement. Everything happens locally on your device: no distances, prices or results are sent to a server, stored or shared, and closing the tab clears the lot. That also means it works fine on a phone at the petrol station.