ChargeEstimateKit

How Long Does It Take to Charge an Electric Car?

Written and maintained by ChargeEstimateKit

Last reviewed:

Quick answer

The quickest estimate is energy needed divided by charging power. For a useful planning number, enter your own battery size, starting charge, target charge, charger power, and efficiency, then leave extra time for taper, temperature, and vehicle limits.

EV Charging Time Calculator

The simple formula

Start with the battery capacity and multiply it by the percentage you plan to add. A 75 kWh battery going from 20% to 80% adds 60% of the pack, or about 45 kWh in the battery. Divide that energy by charger power adjusted for efficiency to estimate hours.

Example estimate

If the charger can deliver 11 kW and charging efficiency is 90%, the effective battery-side power is about 9.9 kW. The 45 kWh session therefore estimates to about 4 hours and 33 minutes. A slower outlet or lower efficiency can change the answer quickly.

Why the real time can differ

The simple formula assumes steady average power, but an EV may reduce power when the battery is cold, hot, nearly full, or limited by the onboard charger. Shared public chargers can also split power across vehicles, so the calculator is best used as a planning estimate.

Charging time across lower and higher state-of-charge segments A state-of-charge timeline compares a 20 to 80 percent constant-power baseline with an 80 to 100 percent top-off whose elapsed time can be extended by charging taper. Charging segments need different planning assumptions 75 kWh battery example from the guide 20% to 80% 45 kWh added 80% to 100% 15 kWh added 20% 80% 100% Constant-power baseline About 4 hr 33 min 11 kW at 90% efficiency High-SOC top-off Add time buffer Taper varies by vehicle and conditions
For the guide's 75 kWh example, 20% to 80% adds 45 kWh and has an about 4 hr 33 min constant-power baseline at 11 kW and 90% efficiency. The final 15 kWh has no fixed time here because vehicle-specific taper can extend the top-off.

Example 20% to 80% charging time by battery size and charger power

Battery sizeEnergy added1.9 kW Level 17.4 kW Level 211 kW Level 250 kW DC150 kW DC
40 kWh24 kWhAbout 14 hrAbout 3 hr 36 minAbout 2 hr 25 minAbout 32 minAbout 11 min
60 kWh36 kWhAbout 21 hrAbout 5 hr 24 minAbout 3 hr 38 minAbout 48 minAbout 16 min
75 kWh45 kWhAbout 26 hr 19 minAbout 6 hr 45 minAbout 4 hr 33 minAbout 1 hrAbout 20 min
100 kWh60 kWhAbout 35 hr 5 minAbout 9 hrAbout 6 hr 4 minAbout 1 hr 20 minAbout 27 min

Anonymized session comparison fields

Use this format when comparing a calculator estimate with a real charging receipt or vehicle log. The rows below show the fields to collect; replace them with your own anonymized sessions before publishing a measured-result claim.

VehicleChargerSOC changeTemperatureEstimateRecorded timeLikely difference
Vehicle model and battery sizeHome Level 2, vehicle limit, or station ratingStart % to target %Ambient or battery conditionCalculator result from entered kWh and kWActual plug-in to stop timeEfficiency loss, onboard charger limit, or taper
Daily top-up exampleLevel 2 AC session40% to 70%Mild weatherUsually close to formulaCompare with wall charger logSmall gap often comes from wall-to-battery loss
Road-trip fast-charge exampleDC fast charger15% to 85%Cold, hot, or preconditionedFormula may be optimisticCompare with charging app receiptCharging curve and 80% taper can dominate

Do not label example rows as real measurements unless they come from an actual session record with personal details removed. A strong published comparison should include at least vehicle, charger power, start and end SOC, temperature context, estimated time, actual time, and the likely reason for any gap.

Common mistakes

  • Using total battery size when the session only adds part of the battery.
  • Forgetting efficiency loss when comparing wall energy with battery energy.
  • Assuming the charger can hold peak power for the full session.
  • Using 0% to 100% when the real session is a smaller daily top-up such as 20% to 80%.
  • Missing the vehicle onboard charger limit when using Level 2 AC charging.

Worked examples

20% to 80% daily planning example

A 75 kWh EV going from 20% to 80% adds about 45 kWh to the battery. At 11 kW and 90% efficiency, the estimate is about 4 hours and 33 minutes, which is a useful overnight planning number.

0% to 100% comparison example

A full 75 kWh session at 11 kW and 90% efficiency estimates to about 7 hours and 35 minutes, but real charging near full can be slower and most daily sessions do not start at 0%.

80% to 100% top-off example

Adding the final 20% to a 75 kWh battery is only about 15 kWh, but DC fast charging may taper heavily near full. Treat the final segment as a buffer-heavy top-off instead of a constant-power session.

Source note

DOE AFDC charging references are useful for charging terminology and levels. The exact charging time still depends on the vehicle, charger, battery temperature, and charging curve.

FAQ

Is charging from 0% to 100% a useful estimate?

It can be useful for comparing chargers, but daily charging usually happens between partial charge levels such as 20% and 80%. A 0% to 100% estimate can also be optimistic because many EVs slow down near a high state of charge.

Run the numbers

Use the related calculator with your own vehicle, charger, and price inputs.

EV Charging Time Calculator