EV vs Petrol Cost Calculator

How it works

Compare equivalent vehicles over the same driving plan

Enter purchase prices that already reflect applicable purchase taxes and verified discounts. Use one annual distance and ownership period for both vehicles so the comparison describes the same transport need. Add charger installation to the EV’s upfront cost. Annual maintenance and insurance or other ownership costs are entered separately for each vehicle; a difference in those assumptions can matter as much as the energy price.

Choose metric units for kilometers and liters or US units for miles and US gallons. EV efficiency is always battery energy per 100 selected distance units. Petrol efficiency changes convention: liters per 100 kilometers in metric mode and miles per US gallon in US mode. Switching the unit setting converts the existing distance, efficiency, and fuel-price values so the scenario remains comparable.

Account for charging losses and the home/public mix

The EV input describes energy delivered to the battery. If 10% of purchased grid energy is lost during charging, divide battery energy by 0.90 to estimate electricity bought. This is different from simply adding 10% to battery use. Home and public rates are blended using the entered share of charging at home, with the remainder priced at the public rate.

For example, 15,000 kilometers at 18 kWh per 100 kilometers uses 2,700 kWh at the battery. With a 10% grid-energy loss share, purchased electricity is 3,000 kWh. An 80% home share at 0.15 per kWh and 20% public share at 0.40 gives a blended rate of 0.20, for 600 in annual charging costs. Parking or session fees should be included in your other annual costs when relevant.

Ownership-cost example over five years

Using the example above, a petrol car consuming 7 liters per 100 kilometers uses 1,050 liters over 15,000 kilometers. At 1.50 per liter, annual fuel cost is 1,575. With EV maintenance of 400 and other annual costs of 1,200, EV running cost is 2,200 per year. Petrol maintenance of 800 and other costs of 1,100 give petrol running cost of 3,475.

An EV purchased for 35,000 with a 1,000 charger and a 15,000 final resale value costs 32,000 over five years under those assumptions. A petrol car purchased for 28,000 with a 12,000 final resale value costs 33,375. The modeled EV saving is 1,375. Its 8,000 upfront premium divided by 1,275 annual running savings gives approximately 6.27 years of simple payback, which excludes resale.

Read total ownership and simple payback as different measures

The cumulative-cost chart includes the purchase at year zero and running costs in subsequent years. It subtracts resale only in the final year of the selected ownership period. That final-year drop represents a modeled sale, not a sudden reduction in historical running costs. Positive EV savings favor the EV under your inputs; negative savings favor the petrol vehicle.

Simple running-cost payback asks how long annual operating savings would take to offset the EV’s initial premium. It excludes resale and may fall outside your chosen ownership period. If there is no premium, the tool reports that directly; if EV running costs are not lower, a positive premium has no payback through running savings. Financing, future price changes, time value of money, and exceptional repairs are not automatically included.

EV vs petrol ownership cost: formula and assumptions

EV energy purchased = distance ÷ 100 × battery consumption ÷ (1 − charging-loss share). Ownership cost = purchase + charger + running costs − final resale value.

Prices, distance, and annual running costs stay constant. Metric petrol consumption is liters per 100 km; US fuel economy is miles per US gallon. Purchase prices should include applicable purchase taxes and verified discounts. Financing and time value of money are excluded. Resale is credited only in the final year; simple running-cost payback excludes resale.

Worked example

Reference example currency: USD. These fixed examples do not change with your calculator preferences.

Using the EV vs petrol ownership cost example:

Distance and fuel units

Kilometers and liters

Annual driving distance (km)

15000

Ownership period (years)

5

EV purchase price ($)

35000

Petrol car purchase price ($)

28000

Home charger and installation ($)

1000

EV battery energy per 100 distance units (kWh/100 km)

18

Share of grid energy lost in charging (%)

10

Share charged at home (%)

80

Home charging price per kWh ($)

0.15

Public charging price per kWh ($)

0.4

Petrol consumption (L/100 km)

7

Petrol price ($/liter)

1.5

Annual EV maintenance ($)

400

Annual petrol maintenance ($)

800

Annual EV insurance and other costs ($)

1200

Annual petrol insurance and other costs ($)

1100

EV resale value at end of period ($)

15000

Petrol resale value at end of period ($)

12000

EV energy purchased = distance ÷ 100 × battery consumption ÷ (1 − charging-loss share). Ownership cost = purchase + charger + running costs − final resale value.

Example result

• Positive EV savings favor the EV; negative savings favor petrol. Resale values reduce costs only at the end of the selected ownership period.
• Simple payback excludes resale and may occur after the chosen ownership period. Charging loss is the fraction of purchased grid energy that does not reach the battery.

These are illustrative inputs. Change the values to explore a different scenario.

What to keep in mind

Use one currency throughout. Currency selection changes labels, not exchange rates. Calculate, then save a named scenario in My workspace to keep it in this browser; export a workspace backup to move it to another device.

Formula references

• US Department of Energy: vehicle cost calculator methodology and comparisons (opens in a new tab)

References explain the underlying methods; they do not imply endorsement or individual professional review of Finflo.

Common questions