# AC or DC charging: what is the difference? > AC or DC at the charger: how it affects your charging time and your bill, with worked examples and tips for picking the right charger. Published: 2026-01-27 · Language: en · Source: https://laadpaalvinden.be/en/blog/ac-vs-dc-charging/ Most chargers are labelled AC or DC. Those two letters decide how fast you charge, what you pay and which charger suits your journey. ## What happens with AC charging? The grid supplies alternating current (AC). A battery can only store direct current (DC). With AC charging, the onboard charger in your car does the conversion. That makes the onboard charger the limiting factor: plug a car with a 7.4 kW onboard charger into a 22 kW post and you still only get 7.4 kW. You find AC chargers along the street, in car parks and at workplaces. They usually deliver 11 or 22 kW, enough to add a good chunk of range in a few hours. Your home wallbox is an AC point too. ## And with DC charging? A DC fast charger does the conversion in the unit itself and sends direct current straight to the battery. The onboard charger is bypassed, so the power can be much higher. Fast chargers often start at 50 kW. Along motorways you also find 150 kW or more. How fast your car actually charges still depends on what its battery can take. A car that accepts 100 kW at most does not charge any faster at a 350 kW charger. That maximum does not hold for the whole session either: as the battery fills up, the power drops. How that works is explained in the article on the [charging curve](/en/blog/charging-curve-fast-charging-slows/). ## A worked example Say you want to add 40 kWh and your car can take 11 kW on AC. The charger may offer 22 kW, but your onboard charger sets the limit: - 40 kWh divided by 11 kW is about 3.6 hours. - With a 7.4 kW onboard charger it becomes 40 divided by 7.4, so almost 5.5 hours. At a DC charger averaging 100 kW, the same 40 kWh takes 24 minutes. In practice you rarely hold that average for the whole session, so expect somewhat longer, especially as the battery nears full. Still, the gap between 11 kW and 100 kW is a factor of ten, and you feel it. To work it out yourself: energy (kWh) divided by power (kW) gives the time in hours. The article on [kW and kWh](/en/blog/kw-vs-kwh-charging-speed/) explains those two units in more detail. ## What does the difference cost? DC is almost always more expensive per kWh than AC. You pay for speed and for the pricier equipment. Prices differ per operator and change regularly, so always check the rate in the app or on the charger itself. A hypothetical example to get a feel for it: suppose DC costs one and a half times as much per kWh as AC. Then the same 40 kWh at a fast charger costs one and a half times what it would at the supermarket post. If the AC price for that charge is 10 euro, it becomes 15 euro. You pay about half as much again to save a few hours. If you were going to be parked for those hours anyway, that is a poor trade. ## When to choose which - You are at work, at the supermarket or parked outside your door overnight: AC. - You are on a long drive and want to get going again: DC. - Your battery is nearly empty and you are short on time: DC. - You are in no hurry: AC. A long journey is usually a mix. You charge calmly on AC at home or at your destination, and on the road you use a fast charger for a short stop. For that stop you rarely need to charge to 100%. Why 80% is often smarter is covered in the article on [charging to 80 percent](/en/blog/why-charge-to-80-percent/). ## Common mistakes - You count on the power of the charger. Your car sets the limit. Check the manual for what yours can take on AC and on DC. - You go to a fast charger while the car will sit for hours anyway. You pay more and gain nothing. - You assume your car can charge anywhere. Not every car can use DC, and the plug has to fit too. Check beforehand. - You charge to 100% at a fast charger. The last stretch is slow, and meanwhile you block a bay for others. ## When this does not apply The split is not always as sharp as the labels suggest. Some AC chargers only deliver 3.7 or 7.4 kW, and that varies by location. A car with a small onboard charger charges slowly even at a powerful AC post. Conversely, some DC points top out at 50 kW, which is not a quick stop for a large battery either. So look at the real power of the point, not only at the letters. Check the power and plug type of each charger on the [map](/en/map/). You can read more about the plugs themselves on the page about [plug types](/en/plugs/), and you will find all the quick points on the page about [fast chargers](/en/fast-chargers/).