Calculating Journey Fuel Costs

Converting MPG to L/100km

Divide 282.5 by your MPG figure. A car achieving 40 MPG = 282.5 ÷ 40 = 7.06 L/100km. Most fuel economy figures are given at motorway speeds — expect 10–20% higher consumption in urban driving.

Annual Fuel Cost

To find your annual fuel cost, enter your total annual mileage as the distance. This is one of the highest-value calculations for deciding between car models — the difference in fuel costs over 5 years between a 40 MPG and 60 MPG car can exceed the purchase price difference.

Electric Vehicle Equivalent

Electric cars use kWh per 100km instead of litres. A typical EV uses 15–20 kWh/100km. At £0.28/kWh, that's £4.20–5.60 per 100km — versus £10.50 for a petrol car at 7 L/100km.

Fuel Cost Calculator

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