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EV Charging Time Calculator

Estimate how long an electric car takes to charge. Enter the battery size, the charge level you are starting from and aiming for, and the charger’s power in kilowatts to get the charging time and the range added per hour.

Quick examples
kWh
%
%
kW

Use the lower of the charger’s output and what your car can accept.

%

Energy lost as heat between the wall and the battery; 10% is typical.

mi/kWh
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Charging time6 h 56 min
Energy added to the battery
45 kWh
Energy drawn from the wall
50 kWh
Range added per hour
22.7 mi/h
Charge added per hour
8.6%

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Save a set of inputs you reuse — your usual rate, your loan, your room sizes — and load it back in one tap.

    Your recent calculations

    Results you calculate here are kept on this device so you can come back to them.

      Formula

      Energy added = battery capacity × (target % − start %) ÷ 100
      Charging time (hours) = energy added ÷ (charger power × (1 − losses %))
      Range per hour = charger power × (1 − losses %) × miles per kWh

      How to use it

      1. Enter the battery capacity in kWh.
      2. Enter the starting and target charge levels.
      3. Enter the charger power, or the car’s maximum charge rate if that is lower.
      4. Read the charging time and the range gained per hour.

      Worked examples

      A 75 kWh battery from 20% to 80% on a 7.2 kW home charger with 10% losses

      Energy added to the battery
      45 kWh
      Energy drawn from the wall
      50 kWh
      Charging time
      6 h 56 min
      Range added per hour
      22.7 mi/h
      Charge added per hour
      8.6%

      A 60 kWh battery from 10% to 80% at a steady 150 kW with 8% losses

      Energy added to the battery
      42 kWh
      Energy drawn from the wall
      45.65 kWh
      Charging time
      18 min 16 s
      Charge added per hour
      230%

      Typical charger power

      Level 1 (a standard US 120 V outlet): about 1.2–1.4 kW, adding 3–5 miles of range per hour. Level 2 (240 V, home or public): 3.3–11.5 kW in most homes, up to 19 kW, adding roughly 12–40 miles per hour. DC fast charging: 50–350 kW.

      The slower of the charger and the car sets the rate. A car with a 7.2 kW onboard charger takes 7.2 kW even when plugged into an 11 kW wall unit.

      Why fast charging takes longer than the math says

      This calculator assumes constant power for the whole session. That is accurate for Level 1 and Level 2 charging, but on a DC fast charger the car reduces power as the battery fills, sharply above about 80%. A session to 80% often takes 25–40 minutes in practice even on a high-power charger, and the last 20% can take as long again. Cold batteries also charge more slowly.

      For long trips it is usually quicker to charge from a low level to about 80% and drive on than to wait for 100%.

      Questions people ask

      How long does it take to charge an electric car at home?

      On a 7.2 kW Level 2 charger, taking a 75 kWh battery from 20% to 80% takes about 6 hours 57 minutes. On a 120 V outlet at 1.4 kW the same charge takes about 36–38 hours.

      How many miles of range per hour does a Level 2 charger add?

      A 7.2 kW charger adds about 22–25 miles per hour for a car that gets 3.5 miles per kWh. An 11 kW charger adds about 35.

      How do I calculate EV charging time?

      Divide the kWh you need to add by the charger’s kW, then add about 10% for losses. 45 kWh ÷ 7.2 kW = 6.25 hours, or about 6.9 hours with losses.

      Related calculators

      EV Charging Cost CalculatorWhat it costs to charge an electric car from one level to another.Electricity Cost CalculatorWhat an appliance costs to run per day, month and year.Battery Life CalculatorHow long a battery lasts from its capacity and the load.Trip Time CalculatorDriving time and arrival time from distance, speed and stops.Gas Cost CalculatorFuel used and cost for a trip, split between passengers.