Apple debuted a MagSafe charger alongside the new iPhones last month. The charger attaches to the magnetic ring in the back of the devices, providing up to 15W of charging power. That’s double the speed of the usual 7.5W maximum provided by Qi-based wireless charging systems.
Apple’s $39 MagSafe charger comes sans a power adapter, which requires users to bring their own power adaptor. Apple does sell a 20W power adapter, which oddly enough, is the only charging option that can provide the full 15W of power to the new MagSafe charger.
To prove this, YouTuber Aaron Zollo of Zollotech tested several first and third-party power adapter options with an iPhone 12 Pro and a MagSafe charger, using a meter to measure actual power output. Zollo found that while the Apple 20W power adapter was able to successfully provide a full 15W, but no other power adapter provided the same power.
Below are the results from Zollo’s tests (via MacRumors):
- Apple’s 20W Power Adapter – 15W
- Apple’s 18W Power Adapter – 13W
- Apple’s 96W MacBook Pro Power Adapter – 10W
- Anker 30W PowerPort Atom PD 1 = 7.5W to 10W
- Aukey 65W Power Adapter – 8W to 9W
- Pixel 4/5 Charger – 7.5W to 9W
- Note 20 Ultra Charger – 6W to 7W
It looks as if third-party companies will need to release new chargers that use the same power profile that Apple is using to provide the optimum amount of power before a third-party charger can hit the full 15W with the MagSafe charger.
Zollo also found that Apple is aggressive when it comes to temperature control, so if the iPhone gets warm, the charging power is limited to below 10W.
In Zollo’s testing older iPhones (including the 11 Pro Max and 8 Plus), charged at around 5W using the MagSafe Charger with Apple’s 20W power adapter.