Free Online Calculators
Battery capacity + charge power โ charge time & costs
Find out exactly how long it takes to charge your EV and what it will cost you in electricity. Enter your battery capacity, current charge level, and charger power output. The calculator uses the simple formula: charge time = remaining kWh รท charger power (kW).
Divide the energy you need to add (battery capacity times the state-of-charge gap you want to close) by the actual charging power, then add a margin for losses and for the slower taper near the top of the battery. The limiting factor is always the lower of the charger's output and the car's maximum onboard AC or DC charging rate.
It's the habit of keeping the battery roughly between the lower and upper fifths of its range instead of routinely charging full or running it near empty, which reduces stress on lithium-ion cells. On DC fast chargers it also saves time, because charging speed drops sharply once the pack is well filled.
For a conventional 12-volt starter battery, a short drive tops up only a little and usually won't recover a deeply discharged battery โ a mains charger is needed for that. In an electric car, driving never charges the traction battery; regenerative braking only recovers a fraction of the energy you just used.
On a home wallbox it typically takes a few hours to fill the remaining half, while a DC fast charger can do the same in well under an hour. The exact time depends on battery size, the car's maximum charging rate, the charger's power and the target state of charge.
No โ for daily use most manufacturers recommend a lower daily charge limit and full charges only before long trips. Leaving the pack sitting at full for long periods accelerates capacity loss, though LFP batteries are an exception and should be charged full regularly.
High-speed driving is the biggest drain, because aerodynamic drag rises steeply with speed; cabin heating in cold weather is the second-largest factor. Cold temperatures, hilly terrain, heavy loads, low tyre pressure and roof boxes all add to consumption as well.
Yes, plugging in overnight is sensible in winter โ the car can keep the battery warm and preconditioning runs on mains power instead of the pack. Set a charge limit below full rather than charging to the maximum every night.
After five years a typical EV has lost only a modest share of its original battery capacity, and most packs are still covered by the manufacturer's battery warranty. Mechanically there is little to wear out; brakes last longer thanks to regenerative braking, while tyres, cabin filters and coolant still need regular service.
Yes, but very little โ parked cars lose a small amount per week to standby systems, alarm, connectivity and battery management, often called vampire drain. Losses grow if sentry or preconditioning features stay active, so switch them off before longer parking.
Charging time depends on two main factors: how much energy your battery needs and how fast your charger can deliver it. The basic formula is simple โ divide the energy needed (in kWh) by the charger's power output (in kW) to get hours. For example, charging a 60 kWh battery from 20% to 80% means filling 36 kWh. On a standard 7.4 kW wallbox, that takes roughly 4.9 hours. On a 50 kW DC fast charger, the same session takes under an hour.
Real-world charging is a bit messier. Onboard charger limits, battery temperature, and the tapering effect near full charge all reduce actual speed. That's why this EV charging time calculator factors in your usable battery capacity, current state of charge, target charge level, and charger type โ giving you a practical estimate rather than a textbook answer.
A regular household outlet (Level 1, around 1.4โ2.3 kW) is the slowest option. Adding 36 kWh at 1.4 kW takes over 25 hours โ fine for overnight top-ups on a short commute, but not practical for a larger EV or a quick turnaround. Most EV owners only rely on this as a backup.
A home wallbox or Level 2 charger (7โ22 kW) is the sweet spot for daily use. A 22 kW three-phase wallbox can fully charge a 77 kWh battery from empty in about 3.5 hours, though most home installations are capped at 7.4 kW, bringing that time to around 10โ11 hours overnight. DC fast chargers (50โ350 kW) are built for highway stops โ a 150 kW charger can add 100 km of range in roughly 10โ15 minutes on a compatible vehicle.
Knowing your charger's actual output โ not just its label โ matters a lot. A 22 kW wallbox means nothing if your car's onboard AC charger maxes out at 11 kW. Always use the lower of the two values when estimating electric car charging time. This calculator handles that automatically when you enter your vehicle's maximum AC charging rate.
Beyond time, cost and range added are the two numbers most drivers care about. If your local electricity rate is $0.25 per kWh and you're adding 36 kWh, expect to pay around $9 for that session. Compare that to an equivalent petrol cost of $20โ30 for the same range, and the savings become clear fast.
Range added depends on your vehicle's efficiency. A car consuming 18 kWh per 100 km gains about 200 km of range from 36 kWh. A less efficient SUV at 25 kWh/100 km gains closer to 144 km from the same charge. You can explore all these scenarios instantly at simple-calculator.online without needing to run the math yourself.
Divide the energy you need to add (kWh) by your charger's output (kW). For a 7.4 kW wallbox adding 40 kWh, that's roughly 5.4 hours. Always use the lower of your charger's power and your car's maximum AC acceptance rate.
Yes. Most EVs slow down charging speed above 80% to protect the battery. The last 20% can take nearly as long as the first 80%, which is why many drivers stop at 80% for daily use.
A 7.4 kW wallbox might take 8โ10 hours for a full charge, while a 100 kW DC fast charger can do the same in under an hour. Fast chargers are ideal for road trips; wallboxes suit overnight home charging.