Petrol vs Diesel vs EV Cost Comparison Calculator

How to use this calculator: Petrol vs Diesel vs EV Cost Comparison Calculator

Compare petrol, diesel and electric vehicle running costs using fuel price, electricity rate, vehicle mileage and EV energy consumption. Calculate cost per km, cost per 100 km, monthly cost, annual cost, yearly savings, lifetime savings and EV break-even distance. The example below is calculated by this page's real engine from the displayed inputs.

1. 1Enter the average kilometres you drive every month.
2. 2Use your actual tank-to-tank mileage if possible. Real-world mileage is more useful than brochure mileage.
3. 3The calculator can populate petrol price from the server-side daily fuel-price service based on the selected city.
4. 4Enter the real-world diesel vehicle mileage in km/L.
5. 5The diesel price can be populated automatically from the live fuel-price service.
6. 6Enter the EV's electricity consumption in kWh/100 km.
7. 7Use the actual electricity rate applicable to the charging location. Home electricity tariffs can vary by state, DISCOM, consumer category and consumption slab.
8. 8Charging losses increase electricity drawn from the grid compared with energy stored in the battery.
9. 9The calculator converts petrol, diesel and EV energy cost into ₹/km so all three vehicles can be compared directly.
10. 10The calculator multiplies each cost per kilometre by your driving distance.
11. 11Enter an ownership period to compare cumulative running costs over several years.
12. 12If the EV has a higher purchase price, the optional purchase-price difference can be compared with its annual running-cost saving.

Input guide and example values

Use values from the same measurement basis and time period. Conditional fields appear only when the related option is selected.

Formula, derivation and worked example

This calculator compares the energy running cost of petrol, diesel and electric vehicles on the same distance basis. Petrol and diesel costs are calculated from real retail fuel price and real-world mileage. EV cost is calculated from electricity consumption, charging losses and electricity tariff. The results include cost per kilometre, cost per 100 km, monthly cost, annual cost, yearly savings and long-term running cost. An optional EV purchase-price difference can be used for a simple running-cost break-even estimate.

Understanding the result

Read the main result together with supporting checks, assumptions, limits and intermediate values.

For a manual check, repeat the first equation, confirm the units and change one input at a time.

Assumptions and calculation scope

• Monthly driving distance is assumed to be entered in km/month; converting from another unit before entry avoids changing the numerical meaning of the calculation.
• Petrol vs Diesel vs EV Cost Comparison Calculator applies the displayed Petrol cost/km = Petrol price ÷ Petrol mileage relationship to the entered vehicle & automobile inputs. Factors that are not exposed as inputs or stated assumptions are outside this calculator's calculation scope.

Common mistakes when using Petrol vs Diesel vs EV Cost Comparison Calculator

• Do not mix units for Monthly driving distance (km/month), Annual driving distance (km/year), Petrol vehicle mileage (km/L). A unit mismatch changes the input magnitude even when the typed number looks reasonable.
• Do not replace the displayed Petrol cost/km = Petrol price ÷ Petrol mileage relationship with a different convention without also changing the underlying assumptions; compare like-for-like methods when checking the result.
• Do not treat EV cost per km = ₹1.6/km from the worked example as a universal answer. It belongs to the displayed example inputs and must be recalculated for the actual case.

Next logical calculator

Continue with EV vs Petrol Emission Calculator

Useful next check because both tools use Annual driving distance and Petrol price, while EV vs Petrol Emission Calculator answers a different part of the same workflow.