EV Charging Calculator

Charging an electric car comes down to three numbers: how many kilowatt-hours the battery needs, how fast the charger and the car can move them, and what each kilowatt-hour costs. This calculator works through all three for any battery, from a 1.4 kW wall outlet to a 350 kW fast charger, and turns the result into cost per mile using the car's EPA efficiency rating. Every figure on this page was computed with the same formulas the calculator uses.

Two sister tools take it further. The EV vs Gas Calculator compares a year of charging with a year of gasoline, maintenance included, and the Natural Gas Cost Calculator handles the other large energy bill in many homes. For any other plug-in load, the Electricity Cost Calculator prices an appliance by its wattage.

How long does it take to charge an electric car?

It depends mostly on the charging level. The Department of Energy's Alternative Fuels Data Center (AFDC) groups charging equipment into three kinds:

• Level 1: a standard 120-volt household outlet. AFDC assumes 1.9 kW and about 5 miles of range per hour of charging, and notes that 8 hours at 120 volts replenishes roughly 40 miles for a mid-size EV. On an ordinary 15-amp outlet, where the cord draws 12 amps, the power is 120 V × 12 A = 1.44 kW.
• Level 2: a 240-volt circuit at home, or 208 volts in many commercial buildings. Units range from 2.9 to 19.2 kW, and most residential chargers run at up to 30 amps, which is 7.2 kW. fueleconomy.gov puts the average at about 25 miles of range per hour, with a range from a few miles to around 40 depending on the car.
• DC fast charging: public stations that feed direct current straight to the battery. AFDC notes that DC equipment can deliver up to 500 kW, and both AFDC and fueleconomy.gov quote roughly 100 to 200 or more miles of range per 30 minutes of charging.

The calculator reproduces those federal benchmarks. A car rated 30 kWh per 100 miles gains 4.8 miles per hour on a 1.44 kW outlet and 24 miles per hour on a 7.2 kW Level 2 unit. The total time then depends on how much energy you add: a 20% to 80% charge of a 75 kWh battery takes 34 hours 43 minutes on that outlet and 6 hours 57 minutes on the 7.2 kW charger.

The charging time and cost formulas

Two details matter. First, charging is not lossless. fueleconomy.gov's energy breakdown for electric cars shows charging losses of about 10% of grid energy in combined driving, which is where the default 90% efficiency comes from. Second, the EPA's kWh per 100 miles figure is measured at the wall outlet with Level 2 charging and already includes the losses in the cable and the onboard charger. That is why the range and cost-per-mile lines use grid energy directly instead of applying the efficiency a second time.

Worked example 1: an overnight Level 2 charge at home

Take an EV with a 75 kWh usable battery and an efficiency of 30 kWh per 100 miles, the rating fueleconomy.gov lists for the 2026 Hyundai Ioniq 5 RWD. It plugs into a 7.2 kW Level 2 charger at 20% and is set to stop at 80%. Its onboard charger accepts 11.5 kW, so the charger, not the car, sets the pace.

Five kilowatt-hours, a tenth of what the meter records, turn into heat in the charging equipment and the battery. The session adds about 167 miles for $9.00, which is 5.4 cents per mile or $5.40 per 100 miles. Plugged in at 10 p.m., the car reaches 80% at about 4:57 a.m. Continuing to 100% from the same 20% start would take 9 hours 16 minutes and cost $12.00 in total.

Worked example 2: a fast-charging stop on a road trip

Now the same car pulls into a 150 kW DC fast charger with 10% left, and its battery can accept the full 150 kW up to 80%. The station charges an example price of $0.50 per kWh.

The last 20% delivers less than a third as much energy as the 70% before it but takes almost as long, 17 minutes against 23, because the calculator's taper model lets the power fall from 150 kW at 80% to 15 kW at 100%, an average of about 59 kW over that stretch. The same 58.33 kWh would cost $10.50 at the 18-cent home rate, so the convenience of the fast charger costs $18.67 on this stop. That price gap, more than the time, decides how much road-trip charging changes an EV's running cost.

Charge time by battery size and charger

The table shows a full charge from empty to 100% at 90% charging efficiency, assuming the car accepts the charger's full power. The battery sizes are round examples of usable capacity, which is smaller than the gross capacity some brochures quote.

Two patterns stand out. Level 1 is a top-up tool rather than a way to refill a large battery: even a 40 kWh pack needs 23 to 31 hours from empty. And moving from 7.2 kW to 11.52 kW only helps if the car's onboard charger can take it, because a car limited to 7.2 kW charges at 7.2 kW on any Level 2 station. fueleconomy.gov even lists some 2026 models separately by onboard charger, such as the Chevrolet Equinox EV AWD with an 11 kW or a 19 kW unit.

Why DC fast charging slows down above 80%

A lithium-ion battery cannot absorb energy as quickly when it is nearly full, so cars reduce fast-charging power as the state of charge climbs; AFDC notes simply that charging power varies by vehicle and battery state of charge. Real curves differ from model to model, so this calculator uses a transparent approximation: full power up to 80%, then a straight-line fall to 10% of that power at 100%. Each cell shows the time from 10% to 80%, plus the extra time from 80% to 100%, at 90% efficiency.

Treat the kilowatt column as the average rate your car actually holds, not the number on the charger. Charge rate varies by vehicle model, and an advertised peak is a maximum, not an average. Federal data shows how far below the nameplate typical sessions run: in a Department of Energy analysis of about 2.4 million charging sessions from mid-2020 to mid-2023, which excluded Tesla's Supercharger network, paid DC fast charging sessions averaged 42 minutes and 22 kWh, or about 31 kW on average. That is also why stopping near 80% is the usual road-trip habit: the last 20% buys the least range per minute.

kWh per mile and the cost to charge a Tesla

Efficiency on the EPA label is written as kWh per 100 miles. Divide it by 100 for kWh per mile, take the reciprocal for miles per kWh, and divide 3,370 by it for MPGe, because the EPA counts 33.7 kWh as the energy in one gallon of gasoline. A rating of 30 kWh per 100 miles is 0.30 kWh per mile, 3.33 miles per kWh and about 112 MPGe. Cost per mile is a single multiplication, so you can answer "how much does it cost to charge a Tesla" without knowing the battery size:

The table uses 2026 ratings from fueleconomy.gov (kWh per 100 miles and MPGe as listed, rounded by the EPA), 1,250 miles a month (15,000 a year, the mileage behind the EPA label), the 18-cent home rate and an example public price of $0.50 per kWh.

A 2026 Tesla Model Y Long Range AWD at 27 kWh per 100 miles costs $4.86 per 100 miles on home power and $13.50 at a $0.50 fast charger. Adding 200 miles of range takes 54 kWh: $9.72 at home, $27.00 on the road. Full-size electric pickups use about twice the energy of the most efficient sedans, so their cost per mile doubles too.

The rate you pay moves the result as much as the car does. EIA's residential averages for January to July 2026 range from 12.36 cents per kWh in North Dakota to 46.28 cents in Hawaii, against a U.S. average of 18.19 cents. For a car using 30 kWh per 100 miles:

These are averages across all residential customers in each state. Your own rate, found by dividing the energy-related charges on your bill by the kWh used, can be quite different, especially on a time-of-use plan that prices overnight power below the daytime rate.

How to use this calculator

Enter the usable battery capacity, the charge level the car shows now and the level you want to reach, or tap one of the shortcuts. Pick the charger level, then a power preset or your own kW figure, and enter the maximum rate your car accepts: its onboard charger for Level 1 and Level 2, or its DC limit for fast charging. Leave the efficiency at 90% unless you have measured your own losses. Set your home rate and the price at the public chargers you use, then the car's EPA kWh per 100 miles (the buttons load four 2026 ratings) and your monthly mileage.

The result card shows the charging time, the cost at the matching price, the energy drawn from the grid and the range added. Below it you will find the time and cost to reach 50%, 80%, 90% and 100%, a table of cost per mile, per 100 miles, per full charge and per month at home and in public, and a step-by-step breakdown of the energy flow. The tool is built for new and prospective EV owners sizing a home charger, renters deciding whether a Level 1 outlet is enough, drivers planning road-trip stops, and anyone checking what an EV will add to the monthly electric bill.

Key terms

• kW and kWh: kilowatts measure power, the rate of charging; kilowatt-hours measure energy, the amount stored or used. A 7.2 kW charger running for one hour moves 7.2 kWh.
• Usable capacity: the share of the battery the car lets you charge and drive on. It is the right number for charging math.
• State of charge (SOC): the battery level in percent, as shown on the dashboard.
• Onboard charger: the converter inside the car that turns alternating current from Level 1 and Level 2 equipment into direct current. Its rating caps AC charging speed.
• EVSE: electric vehicle supply equipment, the charging cable and station on the wall or at the curb.
• Charging efficiency: the share of grid energy that ends up in the battery; the rest is lost as heat.
• kWh per 100 miles: the EPA's consumption rating, measured at the wall outlet, so it includes charging losses.
• MPGe: miles per gallon of gasoline equivalent, with one gallon counted as 33.7 kWh.
• Taper: the drop in fast-charging power as the battery fills.

What changes your charging time and cost

• The car's limit. The lower of the charger's and the car's maximum sets the pace. A 19.2 kW station charges an 11.5 kW car at 11.5 kW.
• Battery temperature and state of charge. fueleconomy.gov notes that charge rate depends on the battery's state of charge and the ambient temperature, so winter sessions and nearly full batteries run slower.
• How much you add. Time and cost scale with the percentage you add, and on DC fast chargers the stretch above 80% is the slowest.
• Your rate plan. Tiered and time-of-use rates change the price per kWh by hour or by monthly usage.
• Public pricing. Some public chargers are free, while others charge a flat fee per session, a monthly subscription or by the amount of electricity, according to fueleconomy.gov.

A few habits keep the cost down: charge at home overnight when your utility offers a cheaper off-peak rate, match a new Level 2 circuit to what your car's onboard charger can actually use instead of buying the largest unit, and on road trips leave the fast charger around 80% unless you need the range to reach the next stop.

Federal tax credits for EVs and home chargers in 2026

Federal incentives changed under Public Law 119-21, signed in July 2025. According to the IRS, the new clean vehicle credit of up to $7,500 is not available for vehicles acquired after September 30, 2025, and the previously owned clean vehicle credit (30% of the price up to $4,000) ended for vehicles acquired after the same date. The alternative fuel vehicle refueling property credit, which paid individuals 30% of the cost of home charging equipment up to $1,000 per item in eligible low-income or non-urban census tracts, covered property placed in service from January 1, 2023 to June 30, 2026. A Level 2 charger installed after June 30, 2026 therefore no longer qualifies for that federal credit. State and utility programs are separate, so check with your utility before you buy.

Limitations

This is an energy and cost estimate, not a model of a particular car. It does not know your car's real charging curve, battery temperature or preconditioning, and its DC taper is a simplification. It treats prices as flat per kWh, while many public networks bill by the minute, add session or idle fees or sell subscriptions, and many utilities use tiered or time-of-use rates. EPA efficiency ratings are standardized test results; real consumption rises in cold weather, at highway speeds and with heavy loads, and fueleconomy.gov notes that charging losses vary with the vehicle, the equipment, the battery's state and the weather. Use the results to compare options and plan, and your car's app or your utility bill for exact numbers.

Related calculators

• To compare a year of electricity with a year of gasoline, use the EV vs Gas Calculator.
• For the cost of heating and cooking with gas, use the Natural Gas Cost Calculator.
• To price any appliance by its wattage, use the Electricity Cost Calculator.
• For a gas car's miles per gallon, use the Gas Mileage Calculator, and for a single trip's fuel bill the Fuel Cost Calculator.
• To check the circuit for a Level 2 charger, the Watts to Amps Calculator converts power to current.

Sources

• EIA Electric Power Monthly, Table 5.3: U.S. average residential price 17.30 cents per kWh in 2025, 17.99 cents for the 12 months through July 2026 and 18.31 cents in July 2026 (release of September 24, 2026).
• EIA Electric Power Monthly, Table 5.6.B: residential prices by state, year to date January through July 2026.
• DOE Alternative Fuels Data Center, Electric Vehicle Charging Stations: Level 1, Level 2 and DC fast charging power and range per hour.
• fueleconomy.gov, Charging Plug-in Electric Vehicles: average range added per hour and public charging pricing structures.
• fueleconomy.gov, Where the Energy Goes: Electric Cars: charging losses of about 10% in combined driving.
• fueleconomy.gov, Download Fuel Economy Data and EPA, Fuel Economy and EV Range Testing: kWh per 100 mile ratings include charging losses and are measured at the wall outlet.
• fueleconomy.gov, 2026 electric vehicle ratings and the MPGe definition (1 gallon = 33.7 kWh).
• DOE Vehicle Technologies Office, Fact of the Week #1319: paid DC fast charging sessions averaged 42 minutes and 22 kWh.
• IRS, Alternative Fuel Vehicle Refueling Property Credit and IRS, Credits for New Clean Vehicles: credit amounts and end dates.