Calculator Inputs
Fill in both vehicle profiles, then compare annual energy use, annual running cost, and total ownership cost.
Example data table
This example shows how the calculator can be used for a realistic five-year comparison.
| Scenario | Annual Miles | Gas MPG | Gas Price | EV kWh/100 mi | Home Rate | Public Share | Annual Gas Cost | Annual EV Cost | 5-Year Gas Cost | 5-Year EV Cost |
|---|---|---|---|---|---|---|---|---|---|---|
| Sample commuter setup | 15,000 | 30 | $3.80 | 28 | $0.15 | 20% | $3,150.00 | $1,686.67 | $43,750.00 | $44,433.33 |
Formula used
1) Gasoline energy use
Gasoline gallons per year = Annual miles ÷ MPG
Gasoline energy (kWh-equivalent) = Gallons per year × 33.7
2) Gasoline annual cost
Annual gasoline fuel cost = Gallons per year × Gasoline price per gallon
Total annual gasoline cost = Fuel cost + Annual maintenance + Other annual costs
3) Electric energy use
Battery energy per year = Annual miles × (kWh per 100 miles ÷ 100)
Wall energy per year = Battery energy per year ÷ (1 - Charging loss %)
4) Weighted electricity rate
Weighted electricity rate = (Home share × Home rate) + (Public share × Public rate)
Home share = 1 - Public charging share
5) Electric annual cost
Annual charging cost = Wall energy per year × Weighted electricity rate
Total annual electric cost = Charging cost + Annual maintenance + Other annual costs
6) Ownership comparison
Total ownership cost = Purchase price + (Annual running cost × Ownership years)
Break-even years = (EV purchase price - Gas purchase price) ÷ (Gas annual cost - EV annual cost)
How to use this calculator
- Enter your expected yearly mileage and how many years you plan to keep the vehicle.
- Provide the purchase price, fuel efficiency, and fuel price for the gasoline car.
- Enter the electric car purchase price, energy efficiency, and both home and public charging rates.
- Set the public charging share and charging loss percentage to reflect your real charging pattern.
- Add annual maintenance and any extra recurring costs for both vehicles.
- Submit the form to see annual cost, cost per mile, total ownership cost, and the Plotly chart.
- Use the CSV or PDF buttons to export the result set for reports or planning.
FAQs
1) What does this calculator compare?
It compares annual energy use, fuel or charging expense, maintenance, other recurring costs, and total ownership spending for a gasoline car and an electric car.
2) Why does gasoline energy use show kWh-equivalent?
Gasoline stores energy too. Converting gallons into kWh-equivalent helps you compare energy demand on one common scale, even though the vehicles use energy differently.
3) Should I include public charging?
Yes. Public charging can cost much more than home charging. A realistic split makes the electricity estimate far more useful for real ownership planning.
4) What do charging losses mean?
Charging losses cover heat and power conversion inefficiencies. The car may store less energy in the battery than what your charger draws from the wall.
5) Are EV maintenance costs always lower?
Often, but not always. EVs usually avoid oil changes and some engine-related service, but tire wear, brakes, suspension, and repairs still matter.
6) What affects break-even the most?
Annual mileage, purchase price difference, local fuel prices, charging rates, efficiency, and maintenance gaps usually have the biggest effect on break-even timing.
7) Are insurance and taxes included automatically?
No. Add any custom recurring charges in the other annual costs fields if you want the comparison to reflect insurance, registration, or local fees.
8) Can I compare used vehicles with this tool?
Yes. Enter the expected purchase prices, realistic efficiency values, and annual running costs for the exact used vehicles you want to compare.