Cost per kilometre is the easiest way to compare vehicles and fuels. It is simply the fuel price divided by your mileage. This guide shows illustrative figures using CostMyTrip’s editable defaults for cars, SUVs and bikes.
Fuel cost per km at a glance
| Vehicle | Mileage | Fuel price | Cost per km | Fuel for 300 km |
|---|---|---|---|---|
| Petrol car (hatchback/sedan) | 15 km/litre | ₹105/litre | ₹7.00 | ₹2,100 |
| Diesel car | 18 km/litre | ₹96/litre | ₹5.33 | ₹1,600 |
| CNG car | 20 km/kg | ₹75/kg | ₹3.75 | ₹1,125 |
| Petrol SUV | 10 km/litre | ₹105/litre | ₹10.50 | ₹3,150 |
| Diesel SUV | 13 km/litre | ₹96/litre | ₹7.38 | ₹2,215 |
| EV car (illustrative tariff) | 6 km/kWh | ₹8/kWh | ₹1.33 | ₹400 |
| Petrol bike | 45 km/litre | ₹105/litre | ₹2.33 | ₹700 |
Mileages are CostMyTrip planning defaults and prices are round indicative figures, not live rates. Your own mileage and local price will differ.
How to work it out for your vehicle
Cost per km = fuel price ÷ mileage. A petrol car that gives 15 km/litre with petrol at ₹105 costs 105 ÷ 15 = ₹7 per km. Multiply by your trip distance to get the fuel bill: 300 km × ₹7 = ₹2,100.
Not sure of your real mileage? Use the mileage calculator on our fuel cost calculator page: fill the tank, drive, fill it again and divide the kilometres by the litres.
What changes the number
- Hills: mileage drops on long climbs; the CostMyTrip planner assumes about 15% less in hilly areas and 25% less in mountains.
- Speed and AC: high speeds and the air conditioner both reduce mileage.
- Load: a full car with luggage uses more fuel than the brochure figure.
- EV charging: the tariff depends on the charger and provider. Enter the rate you will actually pay; ₹8/kWh is a planning assumption, not a verified home or public tariff.
Don't forget tolls
Tolls are separate from fuel. CostMyTrip uses an editable ₹2/km allowance on plains; it is not a verified average or a plaza-based quote; see our FASTag guide.
Common questions
What is the petrol cost per km for a car in India?
At 15 km/litre and ₹105 per litre, a petrol car costs about ₹7 per km. Divide your local petrol price by your car's real mileage for your own figure.
Is CNG cheaper than petrol per km?
Usually yes. At 20 km/kg and ₹75/kg, a CNG car costs about ₹3.75 per km, compared with about ₹7 for a petrol car at 15 km/litre. CNG availability on your route should be checked.
What is the cost per km of a bike?
At 45 km/litre and ₹105 per litre, a petrol bike costs about ₹2.33 per km.
Use cost per kilometre to test the decision
At an illustrative ₹100/litre, a vehicle achieving 15 km/litre costs ₹6.67/km for fuel. At 12 km/litre it costs ₹8.33/km. Over 500 km, that difference is about ₹833. This arithmetic explains why your own observed mileage can be more useful than an advertised test figure.
Petrol and EV: keep the units separate
For an electric vehicle, ₹/kWh divided by km/kWh gives ₹/km. A hypothetical ₹20/kWh charge at 6 km/kWh is ₹3.33/km before charging losses or session fees; ₹8/kWh at the same efficiency is ₹1.33/km. Neither rate is a verified tariff. Use the charger’s displayed pricing and consider the charging plan for the route rather than assuming every kilometre uses a home rate.
A small fuel saving may not justify a detour
Buying 30 litres at ₹2/litre less saves ₹60. A 10 km detour at ₹7/km uses ₹70 of fuel before counting your time. Compare the whole detour cost rather than the pump price alone. The fuel calculator lets you change distance, mileage and unit price together.
Fuel cost is not the full cost of vehicle ownership. Servicing, tyres, depreciation, finance and insurance are separate; include an agreed allowance if comparing long-term ownership or reimbursing a friend.
Worked examples and planning analysis by CostMyTrip Team · 24 October 2026. Hypothetical amounts explain the method; they are not available fares, room quotes or activity prices.
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