How to Calculate Your Car’s MPG and Which Cars Have the Best?

When it comes to miles per gallon (MPG), it’s often the case that the manufacturer figure is very different from the real-world average. So how do you figure out your car’s true MPG? And how easy is it to improve it?

In this guide, we’re showing you how to calculate your car’s MPG, before explaining what different MPG figures mean. We’ll also look at the most fuel-efficient cars on the market right now, and some of the useful ways to improve your car’s MPG rating.

    • Figuring out car mpg

      How to Calculate Your Car’s MPG

      While most modern cars provide an average MPG, calculating it yourself can be more accurate. It’s great practice for those looking to save on fuel costs, as you can adjust your driving style to improve your MPG between fill-ups.Of course, that’s not the complete picture, and a whole range of other factors affect your car’s efficiency rating. But if you want to find the most efficient way of driving – say if you’re a commuter – it’s an interesting way to get a little more mileage from tank of fuel.

      What’s the Difference Between Urban, Extra Urban and Combined MPG?

      When searching for new cars, you may be presented with a range of MPG figures, including Urban, Extra Urban, and Combined. But what do they mean?

      Urban MPG

      Urban MPG reflects a car’s efficiency during in-town driving. It’s based on the Urban Cycle Test, which manufacturers use to calculate a car’s MPG during slow, stop-start driving.

      During the Urban Cycle Test, cars are driven over a 2.5-mile route with stop-start zones and a 31-mph maximum speed limit, to mimic normal inner-city driving. The Urban MPG figure, therefore, gives you an idea of how efficient a car will be if you do most of your driving in town.

      Extra Urban MPG

      Extra Urban MPG might sound like a more stop-start, inner-city version of the above, but it’s actually the opposite. It’s used to show how efficient a car is during in-town driving, as well as some journeys on country roads or the motorway.

      To calculate Extra Urban MPG, manufacturers drive a car over a varied 4.3-mile course, with an average speed of 39 mph, a maximum speed of 75 mph, and stop-start zones. Because this is the type of driving people do most regularly, this is the figure we’d look at over Urban MPG.

      importance of car mpgCombined MPG

      Combined MPG is the figure most manufacturers use to demonstrate a car’s efficiency. As you might have guessed, it’s a combination of Urban and Extra Urban MPG figures, accounting for both in-town and country-road driving.

      Combined is by far the most common way to show a car’s MPG rating. If there’s no mention of Urban, Extra Urban or Combined on a car listing, for example, you can assume that the Combined figure has been used.

      Which New Cars Have the Best MPG Rating?

      If fuel efficiency is important to you when buying a car, it pays to know the makes and models which excel in this area. Because while MPG isn’t everything, it’s still the best way to show how efficient a car is.

      Here are the top 15 new cars with the best MPG figures money can buy, including petrol, diesel and hybrid models.



      Fiat 500 0.9 TwinAir – 74.3 mpg Peugeot 208 1.5 BlueHDi – 73.6 mpg Toyota Prius – 90 mpg
      Volkswagen Up! – 68.9 mpg Vauxhall Corsa 1.5 Turbo D – 70.6 mpg Hyundai IONIQ – 81 mpg
      Peugeot 108 1.0 – 58.9 mpg Skoda Octavia 2.0 TDI – 68.9 mpg Toyota Yaris 1.5 VVT – 80 mpg
      Kia Picanto MPi – 58.9 mpg Rena ult Clio 1.5 dCi – 67.3 mpg Kia Niro Hybrid – 79 mpg
      Suzuki Swift 1.2 Dualjet – 57.2 mpg Citroen C3 1.5 BlueHDi – 67 mpg Lexus UX – 72 mpg

Tips on How to Improve MPG

If you want to make fuel go that extra mile, calculating your average MPG before taking steps to improve it could save extra pennies at the pumps. Here are some tips to help you maximise fuel efficiency and take your average MPG up a gear.

How driving habits can improve car mpg

  • Check the tyres – at least once a fortnight. Having the right tyre pressure for your load can make all the difference in how efficiently your car runs.
  • Ditch weight – carry a load of unnecessary clutter in your boot? Get rid and see your MPG improve.
  • Drive gently for the first five miles – engines consume more fuel when cold. Driving gently for the first five miles will reduce consumption; it’s also good practice for the health of your engine.
  • Change gear at the right time – maximising MPG is about keeping revs to a minimum. Changing gear at the right time will save fuel and make things more efficient.
  • Use cruise control (if you have it) – cruise control is great for staying at the most efficient speed, particularly on the motorway. It avoids unnecessary acceleration and deceleration.
  • Keep the car moving – where possible. Reading the road ahead and avoiding coming to a complete stop is best for fuel economy, as stopping and starting uses fuel more fuel.
  • We hope this guide helps you get your head around MPG and the small things you can do to improve it. At Redex, we’ve developed our fuel additives to support drivers who care about fuel economy and performance. Our fuel system cleaners maximise engine health, so you can get the most from every tank of fuel. For more information, visit the homepage.

5 Ways to Improve MPG Today

6 Ways to Break in a New Car Engine

Should you ‘break in’ a new car? It’s a question with a lot of answers, but most experts and manufacturers agree it’s a good idea. While modern engines are tougher than previous generations, driving gently for the first 1,000 miles or so is still recommended if you want to guarantee the long-term health and performance

20 Weird Driving Laws You Probably Never Knew About

When it comes to following the rules of the road, drivers have a lot to remember. The Highway Code has over 300 separate rules for road users, and more are being added all the time – making it quite tricky to memorise all the do’s and don’ts. Last year, we challenged Redex readers to take

10 Speeding Myths Busted

Speed is one of the most talked-about issues in the world of motoring. It’s also the most controversial, and an area that’s prone to myths and mistruths.