Fuel Cost Calculator
Trip fuel cost from distance, economy and fuel price.
Your figures
Result
How to use this tool
- Enter your own figures over the defaults — Distance, Fuel economy, Fuel price per litre.
- The answer updates as you type. There is no button, and nothing is sent anywhere.
- Change one input at a time to see how sensitive the answer is to it.
Real-world economy is usually 10–20% worse than the manufacturer figure, and worse again in cold weather, heavy traffic or at high speed.
How it works
This takes 3 inputs — distance, fuel economy, fuel price per litre — and returns trip cost, fuel needed and cost per km. The whole calculation happens in this page as you type: there is no submit button, no request, and nothing stored.
A worked example
Worked through with the figures the page already has in it: distance of 500 km and fuel economy of 12 km/L, and the rest as shown, giving trip cost of 75.00. These numbers come from running the calculator’s own code, not from being typed in here, so they cannot drift away from what you see on screen.
Starting from:
- Distance: 500 km
- Fuel economy: 12 km/L
- Fuel price per litre: 1.8
| Result | Value |
|---|---|
| Trip cost | 75.00 |
| Fuel needed | 41.7 L |
| Cost per km | 0.15 |
Fuel Cost Calculator — frequently asked questions
Where do I find my fuel economy?
The manufacturer figure is in the handbook, but your trip computer's long-term average is more realistic.
How do I convert MPG to km/L?
For US MPG, divide by 2.352. For UK MPG, divide by 2.825 — the gallons differ.
Does driving style matter?
Substantially. Hard acceleration and sustained high speed can worsen economy by 20% or more.
Is this calculator free?
Yes, with no account, no limits and no data collection. It runs entirely in your browser.
Should I rely on this for a financial or medical decision?
No. It is a planning estimate built on standard formulas and stated assumptions. For decisions that matter, speak to a qualified professional who can account for your full circumstances.
Is this calculator accurate?
The arithmetic is exact — it uses the standard formula. What limits accuracy is the assumptions: the figures you enter, and factors the formula does not model such as fees, taxes and rule changes.
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Nothing is sent anywhere. The figures you type stay in this page and are never transmitted or stored — how that works.
Disclaimer. The formula is exact; the answer is only as good as the figures and assumptions above. Not financial, tax, medical or legal advice. Full disclaimer.