Petrol, CNG, hybrid or EV: calculate the running-cost break-even
By Let’s Pick My Car · Published
A lower cost per kilometre does not automatically mean a cheaper car to own. Divide the extra purchase cost by the saving per kilometre to estimate break-even distance, then check whether you will drive that far during ownership. Include charging or refuelling access in the decision.
Calculate cost per kilometre on comparable assumptions
For petrol or diesel, divide the price per litre by expected kilometres per litre. For CNG, divide the price per kilogram by kilometres per kilogram. For an EV, use electricity paid for at the meter, including charging losses, divided by distance travelled. Certified efficiency and range figures are useful reference points, but they are not promises of your real-world result.
Use the break-even formula
Break-even kilometres = extra upfront cost ÷ saving per kilometre. In a fictional example, a ₹1,50,000 premium and ₹3/km saving give 50,000 km to recover the premium. At 1,000 km a month that is 50 months; at 500 km a month it is 100 months. If the saving is zero or negative, there is no fuel-only break-even.
What does that calculation leave out?
Fuel-only break-even excludes financing, insurance differences, maintenance, resale value, charger installation and changes in energy prices. Match equipment and gearbox when comparing purchase prices; otherwise part of the premium may be paying for a different trim. Run a low-mileage and a high-energy-price scenario before relying on savings.
When should you investigate each option?
Petrol is worth considering when your annual distance is low or you want familiar refuelling. Investigate CNG when stations fit your routine, while checking luggage space and gearbox availability. Compare a strong hybrid’s premium with your traffic use. For an EV, first establish dependable charging, installation permission and the public-charging options on journeys you actually take.
How to use the site’s estimates
Our guides distinguish certified figures from planning assumptions. Check the exact powertrain, battery, charging conditions and warranty terms in the linked sources. Use your own expected efficiency and local energy prices for the final decision. A favourable running-cost estimate cannot settle comfort, range suitability or ownership uncertainty by itself.
Sources and next steps
These guides explain our buying approach and calculation methods. Worked examples are illustrative. Model facts and their original source-check dates are available in the linked car guides.