Magsafe Charger HeroSource: Joe Wituschek/iMore

What you need to know

  • There's a new MagSafe charger for iPhone 12 this year.
  • The charger offers users up to 15W of power.
  • This can only be achieved when paired with a 20W charging adapter.

Apple's MagSafe charger for iPhone 12 only offers 15 watts of power when paired with a 20W power adapter, according to the latest tests.

Zollotech (Aaron Zollo) has put the new magnetic charger through its paces over on YouTube using a power meter to determine the actual power output of the device.

Zollo has confirmed that Apple's MagSafe charger can only charge at its maximum output of 15W when paired with Apple's 20W charger. Testing revealed that using the charger with an 18W adapter like the one shipped with the iPhone 11 Pro offered a slightly lower power output of around 13W. Performance was noticeably worse using third-party accessories.

The testing reflects Apple's own website, which has previously confirmed that you'll need a 20 watt iPhone 12 charger to get the most out of the new accessory:

Connect the USB-C connector on your MagSafe Charger to a 20 watt (W) or greater Apple USB-C power adapter. Your MagSafe Charger needs a power adapter of at least 12 W of power, and your iPhone charges less quickly when using a power adapter that provides less than 20 W. You can also connect to a USB-C port on a Mac or to third-party adapters that comply with applicable safety standards.

It has already previously emerged that Apple's 18W charger from last year does not officially support fast charge on the iPhone 12. According to Apple's website, you also need this 20W power adapter to fast charge the device, unofficially, our early testing indicates charging with the 18W adapter offers similar charging times.

Whilst the MagSafe wattage may be restricted by the power adapter you're using, our intial testing shows there might not be that much difference. Some numbers:

  • 18W charges more than 50% in 30 minutes
  • 20W charges more than 50% in 30 minutes
  • 18W with MagSafe about 30% in 30 minutes
  • 20W with MagSafe about 30% in 30 minutes

Apple introduced MagSafe as a new way to charge the iPhone 12, along with a range of MagSafe accessories including the charger and a new Apple Wallet, you can see our roundup of the best iPhone 12 chargers here.