Your MacBook only charges when it is off or asleep. As soon as you use it, the percentage stays the same or even drops, while the charger is plugged in. That is a clear sign: the MacBook receives less power than it uses. This article explains why and how to fix it, from a charger that is too weak to a worn battery or a problem in the charging circuit.
Blue Apple repairs MacBooks in Amsterdam, including charging problems. Start with the simple steps below.
Why does it charge when off?
When the MacBook is off or asleep, it uses almost no power. Then everything the charger delivers goes into the battery. When you work on it, much of the power goes to the chip, screen and fan. If the charger delivers less than the MacBook uses at that moment, nothing is left to charge, or the battery has to help out.
Cause 1: the charger is too weak
This is the most common cause. For example a 30 watt charger on a MacBook Pro that expects 96 or 140 watts, a phone charger, or a USB-C hub that passes on only part of the power. Check how many watts the charger delivers and compare that with the charger that came with your MacBook. See which charger fits my MacBook.
In System Information, Power, under AC Charger Information, you see how many watts the connected charger delivers.
Cause 2: the cable
A USB-C cable rated for only 60 watts limits a stronger charger. A damaged cable can also pass less. Try the original cable or a cable rated for 100 watts or more.
Cause 3: heavy apps
With video editing, gaming or many tabs at once, even the right charger can sometimes just not keep up, especially on a MacBook Pro at full power. Check Activity Monitor, Energy tab, for apps demanding a lot. See Activity Monitor explained.
Cause 4: a hub or dock
If you charge through a hub or dock, it keeps part of the power for connected devices. Try connecting the charger directly to the MacBook.
Cause 5: the battery or charging circuit
If the MacBook still only charges when off with the right charger and cable, the battery may be worn, or there is a problem in the charging section of the logic board. Check battery health in System Settings, Battery. If it says "Service Recommended", the battery is due for replacement. See checking battery health.
Step by step
- Use the original charger and cable, directly on the MacBook.
- Try another port, or MagSafe if your MacBook has it.
- Restart the MacBook. On an Intel MacBook an SMC reset may help; see resetting the SMC.
- Check in System Information, Power how much power comes in.
- Close heavy apps and see whether it charges then.
A different message?
If the MacBook says "Not Charging", read MacBook says "Not charging". That can also be a setting where macOS pauses charging temporarily to protect the battery.
What we do at Blue Apple in Amsterdam
We measure what the charger delivers, test the cable, port and battery, and look at the charging section of the logic board. You hear beforehand what is needed and what it costs. More on our page about MacBook battery replacement.
Frequently asked questions
Is it bad if the battery drains a little on the charger during work?
With heavy work and a charger that is too weak, that is normal. Preferably use a charger with enough wattage.
Can I use a stronger charger than needed?
Yes. The MacBook only takes what it needs.
Does my MacBook charge slowly through a monitor?
USB-C monitors often deliver 65 or 90 watts. For a large MacBook Pro that may be too little.
