What Do All the Numbers on an Electric Car Charger Screen Mean?

What Does kW Mean on an Electric Car Charger?

kW (kilowatts) is your charging speed right now. Think of it like water pressure. The higher the number, the faster energy flows into your battery. This is the single most useful number on the screen.

Important: the kW number on screen changes during your session. Your car controls the charging speed, not the charger. A 150 kW charger will not deliver 150 kW if your car can only accept 100 kW, or if your battery is already above 80%. The number you see is what is actually happening right now, not the charger's maximum capability.

What Does kWh Mean on an Electric Car Charger?

kWh (kilowatt-hours) is the total amount of energy delivered during this charging session. If kW is water pressure, kWh is how many liters have filled the bucket. This number only goes up during your session.

Your car's battery capacity is also measured in kWh. A car with a 77 kWh battery that shows 14.3 kWh on the charger screen has received 14.3 kWh of energy so far this session. That does not mean your battery is at 14.3 kWh total. It means 14.3 kWh was added during this particular charge.

This number is also what you pay for. Most charging networks price electricity per kWh. If the rate is 0.40 EUR/kWh and you charge 30 kWh, you pay 12 EUR. Some networks charge per minute instead, which can be more expensive if your car charges slowly.

What Does the Percentage on a Charger Screen Mean?

The percentage is your battery level, also called State of Charge (SoC). 80% means your battery is 80% full. This is the same number you see on your car's dashboard.

Most drivers aim to charge to 80% on fast chargers. Above 80%, the charging speed drops dramatically to protect the battery. Charging from 80% to 100% can take nearly as long as charging from 10% to 80%. For daily driving, the 20-80% range is the sweet spot for battery health and charging efficiency.

Not all charger screens show the percentage. Some only show kW and kWh. In that case, check your car's dashboard or app for the current battery level. The charger gets this information from your car, so if the charger does not display it, it is not a problem. Your car always knows its own battery level.

What Do Voltage (V) and Amps (A) Mean on a Charger?

Voltage and amps are technical details most drivers can safely ignore. They are the components that make up the kW number. Volts multiplied by amps equals watts (and divided by 1,000 gives you kilowatts). The charger screen shows them for completeness, but the kW number tells you everything you need to know about your charging speed.

One thing worth knowing: newer EVs with 800-volt battery architecture (like the Porsche Taycan, Hyundai Ioniq 5, and Kia EV6) can charge significantly faster than older 400-volt cars on the same charger. If you see "800V" on the screen, your car is using its higher voltage capability to charge faster. If you see "400V," it does not mean anything is wrong. Most EVs on the road today use 400-volt systems and charge just fine.

What Do Session Time and Estimated Time Remaining Mean?

Session time shows how long you have been charging. Estimated time remaining shows how long until your target battery level. Both are straightforward, but the "time remaining" estimate is exactly that: an estimate.

The estimate can jump around because charging speed changes throughout the session. If you start at 150 kW, the estimate might say 20 minutes. As the speed drops above 60-70%, the estimate might increase. This is normal. The estimate recalculates based on the current charging speed, which keeps changing. Do not plan your stop down to the minute based on this number. Give yourself a 5-10 minute buffer.

What Do Cost per kWh and Session Cost Mean?

Cost per kWh is the price you pay for each unit of energy. Session cost is your running total. This is how most chargers price electricity, and it is the fairest method because you pay for exactly what you receive.

Prices vary enormously by network, country, and time of day. In Europe, public DC fast charging typically costs 0.35-0.79 EUR/kWh. In the US, prices range from $0.30-0.60/kWh. Home charging is almost always cheaper, often 0.10-0.30 EUR/kWh depending on your electricity rate.

Some networks charge per minute instead of per kWh, or add an idle fee if you leave your car plugged in after it finishes charging. Per-minute pricing penalizes cars that charge slowly, so check the pricing model before you start. The charger screen or the network's app usually shows the rate before you begin a session.

Why Does the EVcourse Scanner Help with Charger Screens?

One scan explains all the numbers in context, no matter the charger brand or language. Charger screens come in dozens of different layouts. Some show five numbers, some show ten. Some use abbreviations. Some are in a language you do not speak. The EVcourse scanner reads whatever is on the screen and explains it in plain language.

Point your phone at the charger screen, and EVcourse identifies every number, status message, and error code on display. Instead of Googling "what does 400V mean on charger," you get an instant, contextual explanation. It works with any charger brand, any screen layout, and any language. Free on iOS. Android coming soon.

Frequently Asked Questions

The Bottom Line

You only need to watch two numbers: kW (your speed) and % (your battery level). Everything else on the screen is supporting detail. kWh tells you how much energy you have received. Voltage and amps are technical plumbing. Session cost tells you what you are paying. Time remaining is an estimate that jumps around.

Once you understand these numbers, charger screens stop being intimidating. They are just telling you how fast energy is flowing and how full your battery is. That is it. If a screen ever shows something you do not recognize, scan it with EVcourse and get an instant explanation. See also: 5 charger screens that confuse everyone and why charging slows after 80%.

EVcourse is not affiliated with, endorsed by, or sponsored by any of the vehicle manufacturers or charging networks mentioned on this page. All trademarks and brand names belong to their respective owners. Charging speeds, costs, and specifications vary by vehicle, charger, region, and conditions. Information is approximate and subject to change. Always refer to your vehicle's manual for specific charging recommendations.