Fuel mileage formula
Mileage (km/l) = distance driven ÷ litres used
Example: 450 km ÷ 30 litres = 15 km/l
Free automotive calculator
Car mileage calculator for fuel and electric vehicles
Calculate actual mileage in km/l, fuel cost per km, EV efficiency in km/kWh, charging cost and estimated monthly running cost using your own trip readings.
Core formula
Distance driven ÷ energy used
Use litres for km/l or kilowatt-hours for km/kWh.
Your trip data
Calculate real-world efficiency
Fuel cost formula
Cost per km = fuel price ÷ mileage
Example: ₹105 per litre ÷ 15 km/l = ₹7 per km
EV efficiency formula
Efficiency (km/kWh) = distance driven ÷ energy used
Example: 450 km ÷ 75 kWh = 6 km/kWh
Accurate measurement
How to calculate actual car mileage with the full-tank method
The dashboard mileage display is useful for trends, but a tank-to-tank calculation gives you an independent real-world measurement. Run the test across normal traffic, speeds and routes instead of choosing an unusually easy journey.
- 1Fill the fuel tank to the automatic nozzle cut-off and note the odometer reading.
- 2Drive normally for a meaningful distance. A longer test usually reduces refill variation.
- 3Refill to the same cut-off point and record the litres added and ending odometer.
- 4Subtract the odometer readings, then divide distance by litres added.
- 5Repeat the calculation over several refills and use the average for planning.
EV measurement
How electric car mileage and efficiency are measured
Electric cars do not consume litres, so their closest mileage equivalent is kilometres per kilowatt-hour. A higher km/kWh value means the vehicle travels farther on the same energy. Consumption may also be shown as kWh/100 km, where a lower value indicates better efficiency.
| Metric | Calculation | How to read it |
|---|---|---|
| km/kWh | Distance ÷ energy | Higher is more efficient |
| kWh/100 km | Energy ÷ distance × 100 | Lower is more efficient |
| ₹/km | Energy cost ÷ distance | Lower means cheaper energy use |
Real-world variation
Why mileage changes between trips
Real-world efficiency is not a fixed vehicle number. Compare like-for-like journeys and use a multi-trip average before making a fuel or charging budget.
Traffic and idling
Stop-start traffic and long idle periods reduce fuel mileage. EVs avoid engine idling but still use energy for cabin systems.
Speed and acceleration
Rapid acceleration and sustained high speed increase the energy needed to move the vehicle.
Tyres and payload
Low tyre pressure, roof carriers and extra load increase rolling or aerodynamic resistance.
Weather and climate control
Extreme temperatures, air conditioning, cabin heating and battery conditioning affect consumption.
Mileage questions
Car mileage calculator FAQs
Practical answers about fuel mileage, EV efficiency, cost calculations and real-world testing.
How do I calculate the actual mileage of my car?+
Subtract the starting odometer reading from the ending reading to find the distance driven, then divide that distance by the litres of fuel used. For example, 450 km divided by 30 litres equals 15 km/l.
What is the most accurate way to check car mileage?+
Use the full-tank method over a representative route. Fill the tank to the same cut-off point, reset the trip meter, drive normally, refill at the same pump if practical, and divide the trip distance by the litres added during the refill.
How is fuel cost per kilometre calculated?+
Divide the fuel price per litre by the measured mileage in km/l. If petrol costs Rs 105 per litre and the car returns 15 km/l, the estimated fuel cost is Rs 7 per km.
How do I calculate electric car efficiency?+
Divide the distance driven by the energy used in kWh to calculate km/kWh. You can also divide energy by distance and multiply by 100 to express consumption as kWh/100 km.
Is EV efficiency the same as electric car range?+
No. Efficiency describes how far the EV travels per unit of energy, while range estimates how far it may travel on the available battery energy. Battery capacity multiplied by km/kWh gives a simplified full-charge range estimate.
Why is my real-world mileage lower than the claimed mileage?+
Traffic, short trips, idling, aggressive acceleration, high speed, road gradient, tyre pressure, vehicle load, weather and air-conditioning use can all reduce real-world mileage or EV efficiency.
Can I use this mileage calculator for diesel cars?+
Yes. The distance-divided-by-fuel formula is the same for petrol and diesel vehicles. Enter the actual litres consumed and your local diesel price for the relevant cost estimate.
Can I use this calculator for bikes and scooters?+
Yes. The fuel mode works for any vehicle measured in kilometres and litres. The EV mode also works for electric two-wheelers when the energy used is available in kWh.
Does the EV calculation include charging losses?+
It depends on the energy figure entered. Energy measured at the wall usually includes charging losses, while energy reported by the vehicle may not. Wall-meter or charger-session energy is generally more useful for estimating electricity cost.
How often should I calculate vehicle mileage?+
Measure over several normal refills or charging sessions and compare the average. A single short trip can be distorted by traffic, weather, route, refill variation or battery state-of-charge estimation.