Fuel Average Calculator

About this Fuel Average Calculator

The Fuel Average Calculator tells you how far your vehicle travels on one litre of fuel, which most people in Pakistan call the average or the mileage. Enter the distance you drove and the litres you used and it returns kilometres per litre, litres per 100 kilometres and miles per gallon. Add the price of fuel and it also shows the cost per kilometre. A second mode works the other way and estimates the fuel and money you need for a planned trip.

Fuel is one of the largest running costs of a vehicle, and a small change in the average has a large effect over a year. A car that returns 14 kilometres per litre instead of 16 uses roughly 14 percent more fuel for every kilometre. By measuring your real average from time to time, you can notice problems such as low tyre pressure or a clogged filter early, compare vehicles honestly and budget for trips without guessing.

For related tasks, try Fuel Economy Converter, Speed Converter or Pace Converter.

How the calculation works

Fuel average in kilometres per litre equals the distance driven divided by the litres of fuel used. Litres per 100 kilometres equals 100 divided by the average. Cost per kilometre equals the price of one litre divided by the average, and the cost of a trip equals the litres used multiplied by the price per litre. To plan a trip, the fuel needed equals the planned distance divided by your usual average. Kilometres per litre multiplied by 2.352 gives US miles per gallon, and multiplied by 2.825 gives UK miles per gallon.

How to use it

1. Fill the tank completely, note or reset the trip meter, and drive as you normally do.
2. Fill the tank completely again, then enter the kilometres driven and the litres that you added, plus the price per litre if you want costs.
3. Press Calculate to see the average, litres per 100 km and cost per km, or switch to trip mode to estimate the fuel and cost of a planned journey.

Practical example

Suppose you drive 420 km and then add 28 litres to refill the tank. The average is 420 divided by 28, which is 15 km per litre, or 6.67 litres per 100 km. At an illustrative price of 270 per litre, the cost is 18 per kilometre, and the 420 km cost 7,560 in fuel.

For a trip of 600 km in a car that gives 15 km per litre, the fuel needed is 600 divided by 15, which is 40 litres. At 270 per litre, the trip costs 10,800, and it is sensible to add about 10 percent as a buffer for traffic and detours.

Things to double-check

Use the full-tank method on at least two or three tanks, because one measurement can be affected by the way the pump stops or by a different filling level. Always fill at the same pump if possible and wait for the same click. The fuel price you enter is only used to show costs, and the tool does not know or fetch current prices.

What fuel average means

Fuel average, called mileage in everyday speech, is the distance a vehicle covers on a fixed amount of fuel. In Pakistan and India it is usually given as kilometres per litre, in Europe as litres per 100 kilometres, and in the United States as miles per gallon. A higher kilometres per litre figure is better, while a lower litres per 100 kilometres figure is better, which confuses many people. The calculator shows all of these measures from one pair of inputs, so you can compare an advertisement in any unit with your own result.

The full-tank method

The most reliable way to measure your average is to fill the tank until the pump clicks off, write down the odometer reading or reset the trip meter, and drive as usual. At the next fill, again stop at the first click and note the litres added. Those litres are what the engine used since the last fill. Divide the distance by those litres. Do not top up after the click and do not compare fills made at different pumps if you can avoid it, because a small difference in the filling level changes the answer by a few percent.

Kilometres per litre, litres per 100 km and MPG

The three units are linked by simple arithmetic. Litres per 100 kilometres equals 100 divided by kilometres per litre, so 15 km per litre is 6.67 litres per 100 km. A US gallon is 3.785 litres and a UK gallon is 4.546 litres, which is why one kilometre per litre equals about 2.352 US miles per gallon and about 2.825 UK miles per gallon. A car that gives 15 km per litre therefore gives about 35.3 US mpg or 42.4 UK mpg. Always check which gallon an advertisement uses.

Cost per kilometre

Cost per kilometre is the most useful figure for a budget. Divide the price of one litre by the average in kilometres per litre. If fuel costs 270 per litre and your average is 15, each kilometre costs 18. A daily commute of 40 kilometres costs 720, and 26 working days cost 18,720 a month. Comparing two vehicles or two routes by cost per kilometre makes the difference visible. Because prices change often, enter the price you actually paid for your last fill.

Planning a trip

Trip mode divides the planned distance by your usual average to estimate the litres you need and then multiplies by the price to estimate the cost. For long journeys add a buffer of ten percent or more, because hills, headwinds, heavy luggage, air conditioning and queues reduce the average. Also divide the trip into legs between fuel stops and make sure that you can reach the next station with a reserve in the tank. Do not let the tank run close to empty in unfamiliar areas or on long motorway stretches.

What affects your average

Many factors act together. Higher speed raises air resistance rapidly, so driving at a steady moderate speed uses less fuel than driving fast. Hard acceleration and braking waste energy. Air conditioning, a heavy load and a roof carrier all increase consumption. Under-inflated tyres increase rolling resistance, so checking tyre pressure each month is one of the easiest ways to protect your average. Engine condition, dirty filters, old spark plugs, wheel alignment and the quality of fuel also matter. Traffic is often the biggest factor in a city.

City and highway driving

Most cars burn more fuel per kilometre in stop-start city traffic than at a steady speed on an open road, because the engine spends time idling and the car must repeatedly accelerate. Hybrids behave differently and can do well in cities. When you measure your average, note whether the tank was mostly city or mostly highway driving, and keep separate records for each. A mixed figure is useful for monthly budgets, while the separate figures help you choose routes and plan trips.

Keeping a fuel log

A small notebook or phone note is enough. At every full tank, record the date, the odometer reading, the litres added, the price and the total cost. After a few months you will have a baseline average, and any sudden drop of more than 10 to 15 percent is a signal to check tyres, filters, the engine and the way you are driving. Logs also help when you sell a vehicle, because a buyer can see that it has been maintained and that its consumption is consistent.

Motorcycles, CNG and other fuels

The calculation does not depend on the vehicle. A motorcycle that covers 280 km on 4 litres has an average of 70 km per litre. For a car on CNG, enter the kilograms of gas and read the result as kilometres per kilogram. For electric vehicles the same idea applies with kilowatt hours, but the figures are usually given in kilometres per kilowatt hour or watt hours per kilometre, so use the energy converter or the power tools for those conversions.

Common mistakes

A frequent mistake is to measure over a very short distance, where a small error in filling changes the result a lot. Another is to top up after the pump clicks or to mix pumps. People also divide litres by kilometres instead of kilometres by litres, and then wonder why the number is tiny. Others compare a city average with a highway figure from the maker, or forget that the dashboard average can be optimistic. Use a full-tank measurement, a long enough distance and the same method each time.

Tips, privacy and limits

Check tyre pressure monthly, remove unnecessary weight, drive smoothly and service the engine on schedule. These habits usually improve the average by a few percent without any cost. The calculator works in your browser, so the numbers that you enter are not sent to Dekuz or stored. It does not fetch fuel prices, and its results are estimates based on the values that you provide. If you notice a result that looks wrong or want another unit added, please use the contact page.

Frequently asked questions