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Fuel Cost Calculator

This calculator combines driving distance, vehicle fuel consumption, fuel price, and number of trips.

Updated · Inputs stay in your browser

Enter your values

Choose the symbol used to display amounts.
Total distance covered per trip.
Average litres used per 100 km.
Price for one litre.
Whole number of trips.

Your values stay on this device. Nothing is sent to Calculate & Decide unless you deliberately use your device's share feature.

What this result means

This calculator combines driving distance, vehicle fuel consumption, fuel price, and number of trips. The results panel explains the main number and the quantities that produced it, so you can check whether the estimate answers your real question.

Formula used

Fuel used = Distance × (L/100 km) ÷ 100 × Trips. Cost = Fuel used × Price per litre.

Step-by-step calculation

  1. Validate every required value and reject values outside the stated field limits.
  2. Convert rates and time periods to the units required by the formula.
  3. Calculate with full JavaScript number precision; do not round intermediate values.
  4. Round only the displayed result and explain the practical meaning.

Worked example

A 320 km trip in a car using 7.2 L/100 km consumes about 23.04 L. At $1.65 per litre, one trip costs about $38.02.

Assumptions and limitations

  • Distance is entered in kilometres and efficiency in litres per 100 kilometres.
  • Fuel price and efficiency stay constant.
  • Idling, traffic, weather, load, and detours are represented only through your efficiency input.

How to use this calculator

  1. Choose a currency symbol when the tool uses money.
  2. Enter values in the units shown beside each field.
  3. Select Calculate, then read both the main result and interpretation.
  4. Change one uncertain input at a time to understand sensitivity.
  5. Use Copy result or Share only when you choose to move the result outside this page.

Common mistakes

  • Entering miles or miles per gallon without converting.
  • Using a dashboard average that does not match the planned route.
  • Forgetting to count a return journey as a separate trip when needed.

Frequently asked questions

Does distance mean one way?

It means the distance covered per trip as you define it. Enter a round-trip distance if appropriate.

Can I use diesel or another fuel?

Yes. Use the matching price per litre and vehicle consumption.

Why can actual cost differ?

Driving conditions and real fuel use vary from the entered average.

Methodology and sources

Formula definitions and edge-case behavior are documented on our Methodology page. No external data is fetched by this calculator.

See the site-wide calculation methodology and editorial standards. Formula errors can be reported through the error-reporting instructions.

Published and reviewed .