Find your vehicle's real-world fuel efficiency.
Divides the distance you actually travelled by the fuel you actually used.
Mileage: Distance ÷ fuel used
The fuel efficiency calculator tells you your vehicle's real mileage from two numbers you record yourself: the distance you drove and the fuel you used. It divides distance by fuel to give kilometres per litre, the figure Indian drivers call 'mileage' or 'average'.
Knowing your true mileage is useful on its own and feeds every other fuel calculation. It shows how far the brochure figure is from your reality, warns you when something is wrong, such as dragging brakes, low tyre pressure or a clogged air filter, and lets you see how driving habits change consumption. Fleet managers use it to spot vehicles or drivers that burn more fuel than the rest of the fleet.
1. Fill the tank to full and reset the trip meter to zero.
2. Drive normally until the tank is about half empty or lower.
3. Fill to full again at the same pump if possible, and note the litres added.
4. Read the distance on the trip meter.
5. Mileage = Distance ÷ Fuel used, in km per litre.
6. Repeat over several fills and divide the total distance by the total fuel for a reliable average.
When you fill to full twice, the second fill replaces exactly the fuel burned since the first, as long as both fills stop at the same level. So litres added equals litres used over the distance on the trip meter. The method needs no fuel gauge reading, which is imprecise. Its main errors come from filling to slightly different levels, which is why a longer distance and several fills give a steadier average.
India quotes efficiency as km per litre, where higher is better. Much of the world uses litres per 100 km, where lower is better. They are reciprocals: litres per 100 km = 100 ÷ km per litre. So 20 km/l is 5 L/100 km and 10 km/l is 10 L/100 km. The L/100 km form makes fuel savings easier to see, because it is proportional to fuel used for a fixed distance.
If one trip gives 20 km/l and another 10 km/l, your overall mileage is not 15 unless you drove equal amounts of fuel on each. The right way is total distance divided by total fuel. For example, 200 km on 10 litres and 100 km on 10 litres gives 300 km on 20 litres, or 15 km/l, but 200 km on 10 litres and 50 km on 5 litres gives 250 ÷ 15, about 16.7 km/l. Averaging the km/l figures directly can mislead.
Nisha reset her trip meter after a full tank, drove 612 km around Chennai over two weeks, and needed 38.4 litres to fill the tank again.
Answer: Fuel efficiency 15.94 km/litre
Estimating fuel used from the fuel gauge, which is not linear and is often inaccurate.
Filling to different levels at the start and end, for example stopping at the first click once and topping up the next time.
Averaging km/l figures from separate trips instead of dividing total distance by total fuel.
Measuring over a very short distance, where small filling errors swing the result a lot.
Trusting the car's trip computer without checking it against a manual fill-to-fill test.
Checking real mileage against the manufacturer's claim.
Spotting mechanical problems early when mileage suddenly drops.
Comparing driving styles, routes or tyre pressures.
Tracking fuel efficiency across a fleet of taxis or delivery vehicles.
Why is my actual mileage lower than the advertised figure?
Manufacturer figures are measured under fixed test conditions in a lab. Real traffic, using the AC, extra load, and your driving style usually bring your real mileage below the claimed number.