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MPG Calculator - What's your car's real fuel consumption?

What's your car's MPG?The Used Car Expert MPG Calculator will help you work out your car's REAL MPG figures, rather than going by the fuel consumption figures provided by the manufacturer.

How to work out your fuel consumption

  • To work out your fuel consumption, drive your car to a petrol station and fill your tank to the top. 
  • Reset your trip mileage to zero and then drive your car as you would normally, and before you run out of petrol, go back to the same petrol station and refill your car with fuel. 
  • Take a note of the number of litres you've used (ask for a receipt at the petrol station and that will give you the exact amount of petrol you've used).
  • Then simply enter the number of litres you've used and the miles (or kilometres) you've travelled and the calculator will give you your MPG. 

Work out your MPG

Want to work out the MPG for your car based on the distance you've travelled and the number of litres of fuel you've used? Use our MPG converter below:

I used     litres of fuel.
and I drove  
Calculated Fuel Consumption =

How can I change my MPG without changing my car?

Driving your car differently can dramtically change your fuel consumption.  Stop/start traffic around town can really bring down your MPG figures - as can driving beyond 70mph!  If you want to reduce the amount of fuel you use there are a  number of things you can do, including:

  • Try to brake as little as possible.   Every time you brake, you're taking energy that has been taken from the fuel to drive the engine and converting it into heat in the brake discs/pads.  So try to think ahead, especially when approaching traffic lights or islands.  You want to be driving as smoothly as possible, avoiding harsh braking or acceleration and avoiding driving in the low gears for prolonged periods.  If you can drive at a constant 60mph you're probably driving as econimically as possible - although this isn't always easy on the UK's busy roads!
  • Turn off your air-con and keep your windows closed when possible.  Of course, on a hot, sticky day it might be better to use a little extra fuel to keep you cool!
  • Keep your tyres inflated to the correct pressure.  Using under-inflated tyres can increase fuel consumption markedly.


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