EV Charging Time Calculator
How long will it actually take? Enter your battery size, current charge, target charge, and charger power to get an estimate.
How this is calculated
Time = energy needed ÷ effective charging power, where energy needed is your battery capacity times the percentage-point gap you're closing, and effective power is your charger's rated power times a charging-efficiency factor (some power is lost as heat). This is a straightforward average-rate estimate; real-world charging isn't perfectly linear.
The biggest source of real-world variance: DC fast chargers deliver close to their rated power up to roughly 80% state of charge, then taper off sharply to protect battery health; the last 20% can take nearly as long as the first 80% on a fast charger. Level 1/2 AC home charging is much closer to linear across the whole range, so this estimate is more accurate for home charging than for fast-charging the last stretch to 100%.
Worked example
Say you've got a 75 kWh battery at 20% charge, plugging into an 11 kW home Level 2 charger, and you want to reach 80% before you leave tomorrow. You need 45 kWh (75 × 60 percentage points). At 90% charging efficiency, your charger effectively delivers 9.9 kW, so 45 ÷ 9.9 ≈ 4 hours and 33 minutes. Plug in overnight and you're covered comfortably, but if you only had a standard 120V outlet (about 1.5 kW), that same 45 kWh would take over 33 hours, which is why a Level 2 charger matters if you regularly need a large charge gap filled quickly.
Frequently asked questions
What charger power should I use for a home Level 2 charger?
Most home Level 2 chargers run 7.4 kW (32A) or 11 kW (48A), depending on your electrical panel and the charger you install. Check your charger's spec sheet; the number on the box is usually the rated output.
What about a standard wall outlet (Level 1)?
A standard 120V outlet delivers roughly 1.2–1.8 kW; enter that as your charger power. Expect a full overnight charge to add only 30–50 miles of range, which is fine for short daily commutes but slow for a large charge gap.
Why does charging slow down as the battery fills up?
Lithium-ion batteries charge fastest when they're emptier and slow down as they approach full to avoid stressing the cells. This tapering is much more pronounced on DC fast chargers than on slower AC home charging. It's also why road-trippers usually charge to about 80% and move on rather than waiting for a full charge; see our road trip planner for that math.
Does cold weather slow down charging?
Yes, noticeably. Batteries charge more slowly in cold temperatures because the battery management system limits charge rate to protect the cells, and some energy goes toward warming the battery pack first. In freezing weather, expect real charging time to run longer than this calculator's estimate; some EVs precondition the battery while driving to a fast charger specifically to reduce this effect.
What's the difference between kW and kWh?
kW (kilowatts) measures the rate of power delivery: how fast energy is flowing. kWh (kilowatt-hours) measures a quantity of energy: how much has been delivered in total. Your charger's power rating is in kW; your battery's capacity is in kWh. Multiply kW by hours to get kWh, which is exactly what this calculator does in reverse to find time.
Can I charge faster than my car's onboard charger supports?
No, your EV's onboard AC charger has a maximum rate (often 7.4, 9.6, or 11 kW) that caps how fast it can accept power regardless of what your wall charger can output. Charging above that rate requires DC fast charging, which bypasses the onboard charger and feeds the battery directly. Check your vehicle's spec sheet for its actual maximum AC charging rate before assuming a more powerful home charger will help.
For a broader look at charging levels and home vs. public charging, see our EV charging 101 guide.