EV Charging Time Calculator

How to use this calculator

1. Enter the battery capacity in kWh and the start and target state of charge.
2. Choose the charging source: a power in kW, or a current in amps on 1-phase 230 V or 3-phase 400 V.
3. Click Calculate charging time for the energy needed and the estimated time.

How charging time is calculated

The energy to add is the usable battery share; the time is that energy divided by the real charging power:

From a current, power is 230 × A on one phase and √3 × 400 × A on three phases. The 0.9 factor allows for charging losses; the final 10–20% charges more slowly as the car tapers the current.

Common AC charging powers

The car's onboard AC charger sets the ceiling — many cars accept only 11 kW AC even on a 22 kW box.

Frequently asked questions

How long does it take to charge an electric car?

Divide the energy you need (battery × charge added ÷ 100) by the charger power. A 60 kWh battery from 20% to 80% is 36 kWh; at 11 kW that is roughly 3.5–4 hours including losses.

How do I convert amps to charging power?

On 1-phase 230 V, power = 230 × amps. On 3-phase 400 V, power = √3 × 400 × amps ≈ 692 × amps. So 16 A gives 3.7 kW single-phase or 11 kW three-phase.

Why does the last part of charging take longer?

Above about 80% the battery management system reduces the current to protect the cells, so the final percent charges much more slowly than the first.