How do you calculate fuel efficiency?

In short, by calculating the distance travelled (Mileage B - Mileage A) ÷ Gallons, will give you your fuel efficiency in miles per galon (MPG).

Subtract mileage A from mileage B. This will give you the number of miles you traveled since the last time you filled up, divide your answer by the number of gallons (gallons B) it took you to fill your tank. This will give you the MPG of your car. 

For litres per 100km, simply dive the fuel used in litres divided by the number of kilometres, then multiply by 100.  The easiest way is to measure your kilometres since your last refuel, then take not of how many litres were used to fill up your tank.

If you have traveled 100 km on the move and at the time of recharging, the vehicle consumed five liters of fuel, your efficiency is 20 kmpl. It is also recommended to download an application where you can store the data and this will help you calculate monthly or annual fuel costs. An easy way to calculate gasoline mileage is to remember the odometer reading or reset the mileage counter when filling up a gas tank. While the exact fuel consumption of your car changes depending on your circumstances (city or highway, road condition, tire pressure, etc.) To calculate fuel consumption, start by writing down how many miles you have in your car and then fill up the gas tank.

Real-world figures are very different and that's how you can correctly calculate the fuel efficiency of your vehicle. Take the average price you pay at pumps per gallon and divide it by the number you found when you calculated the miles per gallon for your car. Not only do these tips save drivers money on fuel and vehicle maintenance, but being aware of fuel economy has many positive environmental impacts. Calculating your own MPG is a good habit because you can see how fuel efficient it is and, therefore, how cost-effective it is.

The fuel gauges are not accurate because there is usually some fuel left in the tank, even when the gauge indicates that it is empty. They then travel until the fuel gauge empties and therefore a figure is achieved that is inaccurate. With the constant increase in fuel prices, more and more drivers are aware of the amount of fuel their car needs. Knowing these amounts can help you improve both fuel efficiency and savings every time you drive.

You've already calculated how many miles (or kilometers) per gallon (or liter) you can drive in your car. For more information on how to get the most out of each tank of gas, read Eartheasy's guide to fuel-efficient driving.

Bethany Pesch
Bethany Pesch

Amateur music geek. Lifelong gamer. Incurable music trailblazer. Subtly charming organizer. Extreme internet evangelist.