Fuel Cost Calculator (Free — Trip, Commute & Car Comparison)
Use this free fuel cost calculator to find out how much a journey will cost in fuel, calculate your monthly commuting costs, or compare the running costs of two different vehicles. Works with kilometres and miles, litres and gallons.
Fuel Cost Calculator
How to Use the Fuel Cost Calculator
Choose your mode — Trip Cost, Monthly Cost, or Compare Two Cars. Enter your distance, fuel efficiency and fuel price, then click Calculate. All units are supported including L/100km, MPG (UK and US) and km/L.
How Fuel Cost Is Calculated
Fuel cost is calculated by dividing your distance by your fuel efficiency to get litres used, then multiplying by the fuel price per litre.
Formula: Fuel Cost = (Distance ÷ 100) × L/100km × Price per litre
FAQs
What is L/100km?
Litres per 100 kilometres is the metric measure of fuel efficiency used in most countries. It tells you how many litres of fuel your car uses to travel 100km. A lower number means a more fuel-efficient car.
What is MPG?
Miles per gallon is the imperial measure of fuel efficiency used in the UK and US. A higher MPG means a more fuel-efficient car.
Does this work for diesel cars?
Yes — just enter your diesel price and your car’s fuel efficiency. The calculator works the same for petrol and diesel.
Can I use this for any country?
Yes — just enter your local fuel price and choose your preferred units. The calculator works worldwide.
Is this calculator free?
Yes, completely free with no sign-up needed.