Whether you are budget conscious, concerned that your driving style is inefficient, or just plain curious, finding out how many miles per gallon you are getting from your car (bike, tractor, tank, whatever...) can be very interesting.
Use our MPG calculator below to get an accurate reading and compare it to what the manufacturer claims.
Our MPG calculator also provides alternative fuel consumption figures including: Km per litre, litres per 100 Km and the US MPG - the US MPG is always a lower figure because the US gallon is 3.79 litres, whereas a UK gallon is 4.54 litres. For example, a figure of 30 MPG (UK) will give a fuel consumption figure of 25 MPG (US).
How to get the most accurate MPG calculation
- Fill your tank to the brim and record your mileage (OR reset your mileage clock)
- Make the journeys that you would like to know your MPG for
- Refill your tank (preferably at the same pump) and record how many litres were needed to refill it. This is how many litres of fuel you have used
- Record your new mileage (OR take note of how many miles since you reset your clock)
- Find out how many miles you have done since your last refill by subtracting your original mileage from your new mileage. (OR If you reset your clock, you already have this figure)
How to manually calculate your MPG
Using the figures obtained from the methods above you can manually calculate your MPG with the following formula:
or you can simply use our MPG calculator above!
Worth noting when calculating your MPG
When measuring your MPG it is worth using the same pump for refills, this will give you the most accurate result possible as pumps can be on a slight slope or calibrated slightly differently.
City driving vs Motorway driving
Your MPG can vary greatly between city driving and motorway driving so do not be alarmed if your MPG has changed dramatically since you last checked it. If you usually only do long steady motorway journeys, and then suddenly you start to do a lot of stop-start city driving, you should expect your MPG to drop.
Repetition breeds accuracy
To get the most accurate reading of how many miles per gallon you are getting out of your vehicle you are best off repeating the process a few times and taking the average. This eliminates the chances of an unusual journey skewing your results.
To get an idea of how your driving style can affect the MPG you are getting in your car, try doing separate tests, one where you are driving aggressively (or as you would normally drive) and then one where you are being particularly careful to drive smoothly - without too much braking or accelerating - and see how much difference it makes.
How to improve your MPG
There are a number of ways you can improve the fuel economy you achieve when driving your car. One is to get a new car that is more fuel efficient! For many people the fuel economy is an important consideration when buying a new car and one you should think about as part of the overall cost of ownership (alongside the price of the car when you buy it, insurance, servicing and maintenance, and depreciation - how much you'll lose between when you buy the car and when you come to sell it). If you're not looking to change your current car in the near future, what can you do to improve the MPG figures you are currently achieving?
Hypermiling is a relatively new word in the dictionary that has been coined to describe the method of driving a car to achieve the best fuel economy possible. The way you drive your car and maintain it can have a significant effect in terms of the MPG you can achieve. Driving your car differently can dramatically 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:
- Avoid using the brakes excessively. Each time you apply the brakes you're taking energy that has been taken from the fuel to drive the engine and get the car moving, and converting that energy into heat in the brake discs/pads. So try to think ahead. When you are coming up to a junction, traffic lights, or maybe a roundabout try to pre-scan and think about the conditions around you. Coast instead of braking heavily. Try to anticipate what others are going to do and when the lights are going to change - that way you can avoid braking and ideally keep the car rolling at all times (it takes a lot of energy to get a stationary vehicle moving again).
- The ideal way to drive economically (other than not driving at all!) is to avoid harsh accelerating and braking. If you can stick to a speed of about 60mph you're probably driving as economically as possible - although this isn't always easy on the UK's busy roads!
- You want to remove anything that is using energy (and therefore your fuel) unnecessarily. Air-con is standard in many modern cars, but having it switched on when you don't need it will unnecessarily burn fuel. So turn off your air-conditioner whenever possible. Also, keep your windows closed as having the windows open affects the aerodynamics of your car and therefore it requires more energy to travel the same distance. Of course, on a hot, sticky day it might be better to use a little extra fuel to keep you cool!
- Roof-racks and other things attached to your car will also affect the aerodynamics - so remove them when they're not in use.
- Under-inflated tyres use markedly more fuel. So ensure you have your tyres inflated to the correct pressure. It's not recommended to over-inflate your tyres beyond the manufacturer's recommended levels as this can be dangerous (increasing the risk of wear and even 'blow-outs').
- Maintaining and servicing your car regularly will also help your MPG figures. Using the thinnest oil that meets the manufacturer's recommendations will reduce the energy that's required to drive the engine and can also reduce wear.
- Don't carry around excess weight (we're not saying you need to lose a few pounds here!) and make sure you remove prams, heavy equipment, golf clubs, etc., from your car when you're not using them.