Fuel & MPG Calculators
Work out fuel costs and efficiency using UK miles-per-gallon (MPG). These tools assume UK imperial gallons, where 1 gallon = 4.546 litres.
Journey cost calculator
Estimate the cost of a single journey using your average fuel economy, distance and the current fuel price.
Use your car's indicated MPG or a value from previous trips. Higher MPG means better fuel efficiency.
Total one-way distance. If it's a return trip, use the total mileage.
For example, 150 pence per litre = £1.50 per litre.
This is an estimate based on MPG × distance × fuel price and assumes steady driving.
MPG from fuel spend
Worked out how much you spent on fuel and how far you drove? Use this to estimate your real-world MPG.
Average price you paid for the fuel (e.g. 150 for £1.50 per litre).
How much you actually paid at the pump for this tank or top-up.
Total miles driven on this amount of fuel (from odometer or trip computer).
Calculated from distance ÷ gallons using UK imperial gallons.
Fuel efficiency converter (MPG ↔ L/100km)
Convert between UK miles-per-gallon and litres per 100 km. Lower L/100km and higher MPG both mean better efficiency.
Enter MPG to see the equivalent L/100km.
Or enter L/100km to see the equivalent MPG (UK).
Uses the UK conversion: MPG = 282.48 ÷ L/100km.