What does 100 km cost in fuel?

You are planning a 250 km trip. Your car uses about 7 litres per 100 km, and petrol costs €1.60 per litre. With those assumptions, fuel costs €11.20 per 100 km and €28 for the trip.

These are worked examples, not current pump prices or typical consumption figures for cars in Lithuania.

Turn litres into euros

Fuel cost per 100 km (€/100 km) = consumption (l/100 km) × price per litre (€/l).

In this example: 7 × 1.60 = €11.20 per 100 km. There is no need to divide by 100 here: consumption is already stated for 100 km.

Trip fuel cost (€) = distance (km) ÷ 100 × consumption (l/100 km) × price per litre (€/l).

So 250 ÷ 100 × 7 × 1.60 = €28. Actual consumption and the price you pay may differ.

What changes the result?

Round the final amount to cents. At 7 l/100 km, a price reduction of €0.10 per litre saves €0.70 per 100 km. To compare that saving with the cost of reaching a cheaper station, see Is cheaper fuel worth the detour?.

Choose the right figures

To find the price you actually paid per litre, divide the fuel payment after discounts by the litres bought: €64 ÷ 40 l = €1.60/l. Leave coffee, car washes and other receipt items out of the fuel amount.

For a future trip, use the price you expect to pay. The Lithuanian Energy Agency’s fuel-price page (in Lithuanian) is a place to check; note the timestamp and any discounts that apply to you.

Use a consumption estimate suited to your car and route. A consistent fill-up history is more useful than one receipt, but fuel bought is not necessarily fuel used: some remains in the tank, and a trip can use fuel bought earlier. A purchase-based average is approximate, especially when fill-ups are missing.

For a car using petrol and LPG, calculate both fuels’ costs over the same total distance, then add them. Our petrol and LPG guide (in Lithuanian) explains why LPG receipts alone are not enough.

This covers fuel only

Insurance, repairs, tyres, the car’s purchase price, depreciation and financing need separate calculations over a consistent period and distance.

MyFuel lets you record one car’s fill-ups and expenses manually, with optional photo attachments. Its summaries are approximate; their period and distance may differ from a particular trip.