EV Charging Cost Calculator

Why charging costs less per mile than gas

An electric car turns electricity into miles at a rate you can measure in cents. A typical EV covers about 3.5 miles on one kilowatt-hour. At a national average residential rate of 18.31 cents per kilowatt-hour, from the EIA monthly electricity update for July 2026, that is about 5.2 cents a mile before charging losses.

A gas car at 30 miles per gallon and $3.30 a gallon runs 11 cents a mile. Even with a 10% charging loss, home charging lands near 5.8 cents a mile, roughly half the cost of gasoline. The Department of Energy's Alternative Fuels Data Center keeps the national data behind these comparisons, including station counts and the cost of different charging levels.

Two things flip that advantage. Public fast charging sells electricity at retail, often 40 to 60 cents a kilowatt-hour, and it can cost more per mile than gasoline. And a high electric rate at home, above 25 cents, narrows the gap fast. That is why the rate you pay matters as much as the car you drive.

Worked example: a 60 kWh battery charged at home

Defaults: a 60 kilowatt-hour battery, an 18 cent rate, 3.5 miles per kilowatt-hour, a 10% charging loss, and 1,000 miles a month.

• Loss factor: 1 divided by 0.90 = 1.111
• Wall energy for a full charge: 60 x 1.111 = 66.7 kWh
• Cost of a full charge at home: 66.7 x $0.18 = $12.00
• Range on a full battery: 60 x 3.5 = 210 miles
• Cost per mile: $12.00 divided by 210 = 5.7 cents
• Cost per 100 miles: $5.71
• Monthly cost for 1,000 miles: $57.14

The same 1,000 miles in the gas car at 30 miles per gallon and $3.30 a gallon costs $110.00. Home charging saves about $53 a month, or $634 a year. The full charge number is the one people remember, because $12.00 to fill a battery that goes 210 miles is the clearest way to see the difference.

Worked example: the same car on a road trip

Public fast charging is convenient and priced for it. Take the same 60 kWh car and the same 1,000 miles, but charge everything at $0.45 a kilowatt-hour.

• Energy drawn at the charger: 1,000 miles divided by 3.5 = 285.7 kWh
• Cost: 285.7 x $0.45 = $128.57
• Full charge on a fast charger: 66.7 x $0.45 = $30.00
• The same 1,000 miles on gasoline: 33.3 gallons x $3.30 = $110.00

On this trip, fast charging costs $18.57 more than gasoline. That is not a reason to avoid an EV, but it is a reason to charge at home the night before and to plan stops around cheaper chargers. Many networks price by the minute rather than the kilowatt-hour, and a charger that slows down above 80% can cost double per mile. The last 20% of a battery is the most expensive electricity you will ever buy on a road trip.

Cost per 100 miles, side by side

Cost per 100 miles is the number that lets you compare a kilowatt-hour against a gallon. The EV figures assume 3.5 miles per kilowatt-hour and a 10% charging loss.

The pattern is clear. Home charging beats gasoline across the range of home rates. Public fast charging only beats a thirsty gas car. If you cannot charge at home or at work, the running-cost advantage of an EV mostly disappears, and that is the single most important thing to check before you buy one.

Charging losses and why they matter

A battery stores less energy than the wall delivers, because some is lost as heat in the onboard charger and the pack. Level 1 and Level 2 charging typically lose about 10% to 15%. That loss is why the calculator multiplies battery size by a loss factor rather than using the battery figure alone.

On a 60 kWh pack the difference is real. At a 10% loss you draw 66.7 kWh from the wall and pay $12.00 at 18 cents. At a 15% loss you draw 70.6 kWh and pay $12.71, a 6% increase on the same fill. Cold weather makes it worse, because the pack has to warm itself and the battery accepts energy more slowly. Budget for a higher loss in winter if you park outside.

Time-of-use rates and off-peak charging

The biggest lever on home charging cost is not the car, it is the rate plan. Many utilities offer a time-of-use plan with a cheap overnight window. Where the standard rate is 18 cents, the overnight EV rate is often 7 to 12 cents.

At 8 cents a kilowatt-hour, the full 66.7 kWh charge costs $5.33 instead of $12.00, and 1,000 miles costs $25.40 instead of $57.14. That is 2.5 cents a mile, which is where the dramatic EV savings stories come from. The catch is the peak rate on the same plan, which is often higher than the standard rate. Run your own numbers, including how much of your household load falls in the peak window, before you switch plans. A timer that starts charging at midnight is the cheapest upgrade you can make.

What the calculator leaves out

Running cost is not the whole cost. Four items sit outside this math.

• Home charger installation. A Level 2 charger plus an electrician runs $500 to $2,000, more if the panel needs work. It is a one-time cost that spreads over years of charging.
• Session and idle fees. Public chargers often add a connection fee and charge for time parked after the battery is full.
• Demand charges. Some commercial rates bill on peak power, which is why fast charging can be priced well above home electricity.
• Battery degradation. Range falls slowly over the life of the pack, which raises cost per mile a little each year.

Even with all four, home charging usually wins on running cost. The point is to compare total cost of ownership, not just the price at the plug, and to know which of these apply to how you drive in practice.