Use the free Fuel Cost Calculator below: your data never leaves your browser — all work happens on your device, and nothing is uploaded to any server.
What a Trip Really Costs in Fuel
Most drivers know the price of fuel and roughly how far they are going, but few can say what a specific trip will cost before they set off. This calculator closes that gap. Enter the distance, your vehicle’s efficiency, and the fuel price, and it shows how much fuel the trip needs, what it costs, and what it costs per kilometre. Tick round trip to double the distance automatically, so a return journey is priced correctly instead of guessed at half value.
Knowing trip cost in advance changes decisions. A weekend trip that costs 45 in fuel feels different from one that costs 120, even if both cover the same distance in different vehicles or at different fuel prices. Sharing fuel costs with passengers becomes fair and simple when you have a number, and comparing driving with a train, bus, or flight becomes possible once driving has a real price attached to it.
How the Calculator Works
Distance can be entered in kilometres or miles, and the tool converts miles to kilometres internally so the rest of the maths stays consistent. Efficiency can be entered in three forms: litres per 100 kilometres, miles per gallon, or kilometres per litre. That flexibility matters, because drivers in different countries think in different units, and converting them by hand is a common source of error.
From distance and efficiency, the calculator works out fuel needed. At 7 litres per 100 kilometres, a 200 kilometre trip needs 14 litres. Multiply litres by the price per litre and you get trip cost: at 1.60 per litre, that trip costs 22.40. The tool also divides cost by distance to give cost per kilometre and cost per 100 kilometres, which are handy for comparing vehicles and for estimating longer journeys from a short known trip.
A Worked Example
Take a 350 kilometre return trip in a car using 6.5 litres per 100 kilometres, with fuel at 1.70 per litre. Fuel needed is 22.75 litres, and the cost is about 38.68. The same trip in a larger vehicle using 11 litres per 100 kilometres needs 38.5 litres and costs about 65.45. The difference, about 26.77 per trip, becomes 1,389 over 52 weekly trips, which is more than many people save by choosing cheaper fuel. Vehicle efficiency, not fuel price alone, usually decides yearly fuel spending.
Now test fuel price instead. If fuel rises from 1.60 to 2.00 per litre, the first car’s trip cost rises from 36.40 to 45.50, an increase of 9.10 per trip. Over a year of weekly trips, that is 473 more. Fuel price shocks hurt, but they hurt efficient vehicles less in absolute money, which is another reason efficiency matters more than most drivers realise.
Why Real Fuel Use Differs From the Book Figure
To measure your real efficiency, fill the tank, reset the trip meter, drive normally until the next fill, and divide litres used by kilometres driven. Repeat over several tanks to average out variations. That measured figure, entered into the calculator, will predict future trips far better than any official rating, because it already includes your car, your roads, and your habits.
Saving Fuel Without Buying a New Car
Small habits save measurable fuel. Keeping tyres at the recommended pressure, removing a roof box when it is not needed, avoiding unnecessary weight in the boot, and driving smoothly with gentle acceleration and early braking all reduce consumption. Air conditioning at motorway speed usually costs less than open windows, while at low speed the reverse can be true. Combining short trips into one longer trip helps, because a cold engine is thirsty and a warm engine is efficient.
Route choice matters too. A slightly longer motorway route at steady speed can use less fuel than a shorter route through congested streets with constant stopping. The calculator prices distance, but it cannot price congestion, so use your measured city efficiency for city trips and your measured motorway efficiency for long trips, rather than one figure for everything.
Frequently Asked Questions
Should I enter fuel price per litre or per gallon? This calculator uses price per litre for all efficiency modes, so if your local price is per gallon, divide it by 3.785 to get the per-litre price before entering it.
Does the calculator include tolls or parking? No. It covers fuel only. Add tolls, parking, and wear costs separately for a full trip cost, because on some routes those exceed fuel itself.
What if I drive an electric vehicle? The fuel maths does not apply directly. For electric trips, use electricity price per kilowatt-hour and consumption per 100 kilometres instead, which is a different calculation from petrol or diesel.
Use the tool above before any long drive, and you will never again guess what the tank will cost.
Disclaimer: The results shown by this tool are ESTIMATES only. They are for education and planning, not financial or tax advice. Your real amounts will differ because rates, taxes, fees and prices change. Talk to a qualified financial or tax professional before you make a money decision.
Related tools
- Calculadora de Costo de Combustible (Spanish version)
- Fuel Efficiency Calculator
- Retirement Savings Calculator