Fuel Cost Calculator

How much will your trip cost in fuel?

This fuel cost calculator works out how much fuel a journey needs and what it will cost, including the return trip and the share for each passenger. It works with kilometres or miles and with km/L, L/100km or MPG.

How to use it

1. Enter the trip distance and choose km or miles.
2. Enter your car fuel efficiency and its unit: km/L, L/100km or MPG (US).
3. Enter the fuel price per litre.
4. Set the number of passengers and tick Include return journey if needed.
5. Read the fuel needed, total cost, cost per person and cost per 100 km or miles. Use Copy summary to share it.

Fuel cost formula

Fuel needed = distance ÷ fuel efficiency and cost = fuel needed × price per litre.

Example: a 250 km trip in a car that does 12 km/L needs 250 ÷ 12 = 20.8 litres. At 1.85 per litre the trip costs about 38.54, or 19.27 each for two people.

Fuel efficiency units explained

Unit	Meaning	Better when
km/L	Kilometres per litre	Higher
L/100km	Litres used per 100 km	Lower
MPG (US)	Miles per US gallon (3.785 L)	Higher

Quick conversions: 10 km/L = 10 L/100km ≈ 23.5 MPG (US).

Ways to cut fuel costs

• Keep tyres at the correct pressure.
• Drive smoothly and keep a steady speed — hard acceleration burns fuel.
• Remove roof racks and extra weight when not needed.
• Share the trip: the calculator shows exactly how much each passenger owes.

Frequently asked questions

How do I find my car fuel efficiency?

Fill the tank, reset the trip meter, drive normally, then refill. Divide the distance driven by the litres added to get km/L.

Can I use a price per gallon?

Enter the price per litre: divide a US gallon price by 3.785.