Skip to content

EV Charging Time Calculator

Charging time depends on your battery size, the charge you add and the charger’s power. Enter your battery capacity, the start and target state of charge, and the charger’s kW to see how long it takes, the energy and range you add, and how that time compares across Level 1, Level 2 and DC fast chargers.

Usable capacity; typical EVs are 40–100 kWh.

Level 1 ≈ 1.4 kW, Level 2 ≈ 7–11 kW, DC fast 50–350 kW.

Assumptions

Wall-to-battery; charging loses ~10–15%.

Only affects range added; typical 3–4 mi/kWh.

Time to charge (start → target)

6.3 h

At a constant charging rate.

Verdict: This charge takes about 6h 18m, adding 147 miles of range — roughly 23 miles per hour of charging.

Get a shareable image
Time
6h 18m
Energy added
42.0 kWh
Range added
147 mi
Charging speed
23 mi/h
Full 0–100% time
10h 31m
  • 1.4 kW (L1)33.3 h
  • 7.4 kW (L2)6.3 h
  • 11 kW4.2 h
  • 50 kW (DC)0.9 h
  • 150 kW (DC)0.3 h
Time to add the same charge across charger powers. DC fast-charge times are optimistic — real charging slows above ~80%.

Assumes a constant charging rate. Real DC fast charging tapers as the battery fills, so high-power times are best-case. Estimate only.

How this is calculated →

Save & compare

Save the current inputs and compare up to 4 side by side. Stored on this device only.

How it works

This calculator estimates how long it takes to charge your EV between two states of charge, at a charger power you choose.

  • Battery capacity and the charge window (start → target SoC) set how much energy goes into the battery.
  • Charger power sets how fast that energy is delivered. We reduce it by a charging efficiency, because some energy is lost converting AC to DC for the battery.
  • EV efficiency turns the energy added into miles of range and an effective charging speed.

The headline is the time for your chosen charge window. The chart shows the same session at different charger powers, so you can see how much faster a higher-power charger is — with the caveat that real DC fast charging slows as the battery fills.

Methodology & assumptions

Results use the inputs you provide plus these defaults. The battery, charge window and charger power are yours to set; the charging and EV efficiency defaults are tied to dated sources and are editable in the calculator.

AssumptionDefaultSource
Battery capacity (default)User-supplied; typical EVs are 40–100 kWh.70 kWh
Charge window (default)User-supplied; the common everyday charging range.20% → 80%
Charger power (default)User-supplied; L1 ≈ 1.4 kW, L2 ≈ 7–11 kW, DC 50–350 kW.7.4 kW (Level 2)
Charging efficiencyWall-to-battery losses for AC charging.90%U.S. DOE Alternative Fuels Data Center (AFDC)
EV efficiency (for range added)Editable; typical 3–4 mi/kWh.3.5 mi/kWhU.S. DOE / EPA — fueleconomy.gov

Full formula, every default and its source: EV charging time methodology.

Worked example

Take a 70 kWh EV charging from 20% to 80% on a 7.4 kW Level 2 charger, at 90% charging efficiency and 3.5 mi/kWh:

  • Energy added: 70 × (80 − 20) ÷ 100 = 42 kWh.
  • Charge time: 42 ÷ (7.4 × 0.9) = 42 ÷ 6.66 ≈ 6.3 hours (about 6h 18m).
  • Range added: 42 × 3.5 = 147 miles, at roughly 23 mi/h.
  • A full 0–100% on the same charger ≈ 10.5 hours.

The same 42 kWh at a 50 kW DC charger would take under an hour in this constant-rate model — but in reality the car slows the charge as it fills, so plan for a bit longer above 80%. Put in your own numbers above.

Frequently asked questions

How long does it take to charge an EV?

It depends on the battery size, how much charge you add and the charger’s power. As a rule, charge time = energy added ÷ (charger power × charging efficiency). A 60% top-up on a 70 kWh battery (42 kWh) at a 7.4 kW Level 2 charger takes about 6 hours; the same top-up at a 50 kW DC charger takes under an hour.

What’s the difference between Level 1, Level 2 and DC fast charging?

Level 1 uses a standard household outlet at about 1.4 kW — slow, but fine overnight for small daily mileage. Level 2 (a 240 V home or public charger) delivers roughly 7–11 kW and fully charges most EVs overnight. DC fast charging (50–350 kW) bypasses the onboard charger to add a lot of range in minutes, but is hard on the battery and tapers as it fills.

Why does charging take longer than the charger’s rated power suggests?

Some energy is lost as heat when AC is converted to DC for the battery, so the power reaching the cells is a bit lower than the charger’s rating. We divide by a charging efficiency (90% by default) to account for that, which lengthens the time slightly versus a naïve energy ÷ power calculation.

How long to add a specific number of miles of range?

Divide the miles you want by the charging speed shown in the result. Charging speed (miles of range per hour) equals your EV’s efficiency in mi/kWh multiplied by the effective charging power. At 7.4 kW, 90% efficiency and 3.5 mi/kWh you add roughly 23 miles of range per hour.

Does battery size affect charging time?

Only through how much energy you add. The time depends on the kWh you put in, not the battery’s total size — so going from 20% to 80% on a bigger battery means more kWh and a longer charge at the same charger power. Charging from 0–100% naturally takes longer on a larger pack.

Why isn’t DC fast charging linear?

To protect the battery, the car ramps charging power down as the pack fills — most noticeably above about 80% state of charge. A 10–80% session is far quicker per kWh than the last 80–100%, which is why this calculator’s high-power times (which assume a constant rate) are best-case figures.

What charging efficiency should I use?

The 90% default is representative of AC charging losses. Level 1 charging is often a little less efficient, and very cold weather increases losses further because the car uses energy to condition the battery. If you know your own figure, edit it in the assumptions.

By EnergyTally Team · Editorial & analysis team

Published
Updated
Review
EnergyTally Team,