Household Figures

EV Charging Cost Calculator

Enter your battery size, how much you charge, and your electricity rate to see what a charge costs.

Usable capacity from the spec sheet.
Energy that reaches the battery. Often 0.85 to 0.9 at home.
Your home rate, or the public charger's price.
Miles per kWh of battery energy.
Cost of this charge: —
Energy added to the battery
—
Energy drawn from the wall
—
Range added
—
Cost per mile
—

Where to find your numbers

Not sure what to enter? Here is where to find each value for your own home. If you cannot find one, leave the example value and treat the result as a rough estimate.

Battery size (kWh)

The usable energy stored in the car's battery, in kilowatt-hours.

  1. Check the owner's manual or the manufacturer's website for your exact year and trim.
  2. Search for "[year] [make] [model] [trim] usable battery kWh".
  3. Use the usable capacity if both usable and total are listed.

Some trims of the same model have different battery sizes, so check yours.

Starting and ending charge (%)

How full the battery is when you plug in and when you unplug.

  1. The car's screen or phone app shows the charge percentage.
  2. Think about a typical charge. Many drivers plug in at 20% to 30% and stop at 80% for everyday use, and charge to 100% only before long trips.

Charging efficiency (0 to 1)

The share of the electricity you pay for that actually reaches the battery.

  1. This is not printed on the car. Home Level 2 charging (240 volts) is often around 0.85 to 0.9, and slow 120-volt charging can be lower.
  2. To measure it, compare the kWh your charger or app reports from the wall with the kWh the car says it added.

If you use a "kWh per 100 miles" figure from the EPA label for the next input, set this to 1, because the EPA figure already includes charging losses.

Driving efficiency (miles per kWh)

How many miles the car travels per kWh of battery energy.

  1. Look at the car's trip screen or app. Many show miles per kWh directly, or kWh per 100 miles (divide 100 by that number).
  2. Or look up your model on fueleconomy.gov (opens in a new tab) and use the kWh per 100 miles, then set charging efficiency to 1.
  3. A typical range is around 2.5 to 4 miles per kWh, depending on the car and conditions.

Electricity rate ($ per kWh)

This is what your utility charges for each kilowatt-hour (kWh) of electricity.

  1. Open your latest electric bill (paper, email, or your utility's website or app).
  2. Look for a line called "price per kWh", "energy charge" or "rate". It is often shown in cents, so divide by 100 (17 cents is 0.17).
  3. If the bill only shows totals, divide the total electricity charges by the kWh used. This quick all-in rate includes fixed fees, so it runs a little high.
  4. If your rate changes by time of day or by how much you use, use an average, or the rate that applies when you use the appliance most.

No bill handy? About 17 cents is a rough US average, so the pre-filled value is a fair start. Rates vary a lot by state and utility, so your own number is better.

See the average residential rate for every state

How it works

Energy added to the battery is battery size times the charge you add. Energy from the wall is that amount divided by charging efficiency. Cost is wall energy times your rate. Range added is battery energy times miles per kWh, and cost per mile is cost divided by range added. To compare with a gasoline car, see the EV vs gas calculator.

Frequently asked questions

How much does it cost to charge an electric car at home?

It depends on battery size, how much you charge, and your electricity rate. For example, adding 36 kWh to the battery (20% to 80% of a 60 kWh pack) takes about 40 kWh from the wall at 90% efficiency, which is about $6.80 at 17 cents per kWh.

What is charging efficiency?

Some energy is lost as heat in the charger, cables and battery, so you pay for more energy than ends up in the battery. Home charging is often somewhere around 85% to 90% efficient, and slower or colder-weather charging can be lower. The default of 0.9 is an example.

Where do I find my battery size and miles per kWh?

Your owner's manual or the manufacturer's spec sheet lists usable battery capacity in kWh. For driving efficiency, divide your typical miles driven by the kWh the battery used, or use the figure on the car's trip display.

What about public fast charging?

Public chargers often cost more per kWh than home charging, and some bill by the minute or add session fees. For a rough comparison, enter the price you pay per kWh at that charger, and use a lower charging efficiency if you want to be cautious.

Related tools

How the numbers are produced: see our methodology.