Mac Charger Wattage Warning? Check Your Charger
Your Mac warns that the charger wattage is too low, and charging crawls or stalls. The charger or cable cannot deliver what the Mac needs. Use the charger made for your Mac, check the cable, and test again.
TL;DR / Quick Fix
Quick fix: switch to the charger and cable that came with your Mac, or a charger rated for your Mac model. Plug it firmly into a working outlet, then check the battery icon after a few minutes. Test again tomorrow and confirm the fix still holds.
Follow these steps
- Use the correct charger. Use the charger that came with your Mac, or one rated for your Mac model. A phone charger may connect, but it cannot charge a laptop properly.
- Check the cable. Use the original cable or a cable rated for laptop charging. A thin or damaged cable can limit power even with the right charger.
- Try another outlet and port. Plug the charger into a different wall outlet, and try another USB-C port on the Mac. A faulty outlet or port can trigger the warning.
- Clean the port gently. Check the charging port for dust or lint, and remove debris gently with dry air or a soft brush. Do not poke the port with metal tools.
- Check charging while the Mac rests. Close heavy apps and let the Mac charge undisturbed for fifteen minutes. Heavy use while charging can outpace a low-wattage charger.
- Replace a suspect charger. If the warning follows one charger across outlets and ports, replace that charger with a proper one. Do not keep using a charger that cannot meet the Mac needs.
What NOT to do
- Do not ignore a wattage warning and keep using a phone charger. Slow charging under load can drain the battery even while plugged in.
- Do not buy the cheapest charger you find. Use a charger rated for your Mac from a trusted maker, with the right wattage.
- Do not force a damaged cable into the port. A frayed cable can damage the port and should be replaced, not forced.
- Do not charge through a hub for testing. Test the charger directly in the Mac first, so a hub power limit does not confuse the result.
Frequently asked questions
What does the wattage warning mean?
The charger delivers less power than the Mac needs for normal charging, so charging will be slow or may stall under load.
Can I use a phone charger in an emergency?
It may add a little charge while the Mac sleeps, but it is not a proper laptop charger for daily use.
Why does charging stop during heavy work?
Heavy work can use more power than a low-wattage charger supplies, so the battery drains even while plugged in.