How it works
Use comparable purchase quotes, and the same number of years and the same distance for both cars. Each car's economic cost adds up depreciation, fees, interest and running costs. The purchase price minus resale already covers the principal, so don't enter your full loan payments as interest. Enter just the interest you'd pay during the ownership period, even if the loan runs longer.
Choose the right energy boundary for the EV's consumption figure. A wall or grid figure already includes charging losses, so no extra adjustment is needed. A battery-only figure gets divided by charging efficiency to estimate what the wall supplies. If you charge in several places, use a blended price, and put fixed subscriptions or recurring fees in the EV's annual non-energy costs.
The formula behind the estimate
Every result starts with a defined model and visible assumptions.
Annual gasoline cost = annual miles ÷ US mpg × price per US gallon Metric gasoline cost = annual km × L/100 km ÷ 100 × price per liter Annual EV wall kWh = annual distance × kWh per 100 distance ÷ 100 For battery-only consumption, divide energy by charging efficiency Vehicle total = purchase price − resale + upfront fees + charger (EV only) + period interest + years × (annual energy + annual other costs) EV cost advantage = gasoline total − EV total
A worked example
At 12,000 miles a year, 30 US mpg and $3.50 a gallon, gasoline costs $1,400 a year. An EV using 30 wall kWh per 100 miles at $0.20 per kWh costs $720 a year. With the default five-year purchase, resale, fee, interest and other-cost assumptions, the gas car totals $36,800 and the EV $35,700, so the EV comes out $1,100 cheaper in this made-up scenario. Different quotes or resale values can flip it.
Is cheaper energy enough to make an EV cheaper to own?
Not on its own. The annual energy row compares fuel and electricity only. The main result also includes lost value, fees, charging equipment, interest and other running costs, so lower energy spending doesn't automatically mean the lower total.
Resale values and annual running costs are your assumptions, not predictions for a particular make. The model doesn't claim every electric car has cheaper insurance or maintenance. Get quotes for the real cars and try both hopeful and cautious numbers.
How do I keep the charging inputs consistent?
A wall-energy rating and a dashboard battery reading measure different things. If you add another loss factor to a figure that already includes charging losses, you'll overstate how much electricity you use. Pick battery mode only when your consumption number was measured at the battery.
The electricity price is per wall kWh. Time-based charging, idle fees, parking, subscriptions and demand charges need an effective unit price or their own annual line. This tool compares gasoline with a battery-electric car; plug-in hybrids split their energy use and need a different calculation.
Questions worth asking
Is an electric car cheaper than a gas car?
It depends on purchase price, resale value, energy rates, how far you drive, insurance, maintenance and financing. Enter matched local scenarios for both cars to see the full ownership totals side by side.
Are charging losses counted twice?
No. Wall-energy mode applies no extra loss, and battery-energy mode divides consumption by your charging efficiency once.
Are incentives and electricity prices updated automatically?
No. Use your own verified purchase price and energy rates. The tool doesn't look up incentives, tax eligibility or local tariffs.
Should I include the entire loan payment?
No. Depreciation already accounts for the purchase principal, so enter only the interest you'll pay during the comparison period, and count fees once.
Can I compare in kilometers and local currency?
Yes. The unit switch converts distance, fuel economy, fuel price and EV consumption together, and eight currencies are available for display. Money isn't exchanged automatically.
This is general information, not personalized financial advice. Read the limitations.
