PetrolCalculator

Fuel calculator

MPG Calculator

Calculate your real-world UK MPG from two odometer readings and the litres needed to refill your tank.

Calculate your MPG

Record your odometer before and after driving, then enter the litres needed to refill your tank.
How this calculation works: miles driven ÷ UK gallons used. One UK gallon equals 4.54609 litres.

What your result means

UK MPG tells you approximately how many miles your vehicle travels per UK gallon. It is most useful when calculated from a measured distance and the litres needed to refill the tank.

Worked example

This example uses the same MPG model as the calculator.

Miles driven
300 miles
Fuel used
30 litres
UK gallons used
6.6

The result is 45.5 UK MPG.

Formula

UK MPG=Miles driven×4.54609Litres used\text{UK MPG}=\frac{\text{Miles driven}\times 4.54609}{\text{Litres used}}

UK MPG and litres per 100 miles

UK MPGLitres per 100 miles
3015.2 litres
4011.4 litres
509.1 litres
607.6 litres

Helpful questions

Does this calculate UK or US MPG?

It calculates UK / imperial MPG, using a 4.54609-litre UK gallon. US MPG uses a smaller gallon, so the figures are not interchangeable. Use the US MPG to UK MPG Converter if you need to compare them.

Why is my real MPG different from the manufacturer figure?

Manufacturer figures are measured under set conditions. Traffic, speed, driving style, load, weather and journeys can all change the MPG you achieve.

How should I measure MPG accurately?

Fill the tank, record the mileage, drive normally, then refill and record the miles and litres. Using a full-to-full measurement makes the result more representative.

Can I convert the result to L/100km?

Yes. Convert UK MPG to L/100km to compare the same consumption in metric units.

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