iOS 27 Code Hints at 33% Higher Charging Rate for iPhone 18 Pro [Rumor]

The iPhone 18 Pro and iPhone 18 Pro Max could support a charging rate 33% higher than their predecessors, based on code discovered in iOS 27 by pdfu.



The figures come from Apple's thermal charging optimizer and are expressed as C-rates, which measure charging current relative to battery capacity. The new Pro models are listed at 2.20C, up from 1.65C. If sustained, that increase could shorten an equivalent fast-charging stage by about 25%.


That calculation does not establish how much faster a full charge would be. Actual charging speeds vary with battery temperature and how much charge remains, so the improvement in everyday use could be smaller.

Battery capacity may also change. Alleged regulatory filings have pointed to a 5,567 mAh battery for the eSIM-only iPhone 18 Pro Max, while the standard Pro model is expected to see only a marginal capacity increase over its predecessor.

Apple's first foldable iPhone does not appear to get the same charging-rate increase. The code lists it at 1.65C, matching the iPhone 17 and iPhone 17 Pro.

The findings also cover models expected in spring 2027. The standard iPhone 18 is listed at 2.20C, matching the new Pro models. The iPhone 18e is also listed at 2.20C, roughly 69% above the estimated 1.30C rate for the current iPhone 17e. Meanwhile, the iPhone Air 2 is listed at 1.65C, up about 27% from the current model's 1.30C.


Apple is expected to unveil the iPhone 18 Pro and Pro Max alongside its first foldable at today's 'Surprise and Shine' event. The September 9 presentation begins at 10 a.m. Pacific / 1 p.m. Eastern. Follow our live blog for coverage of the announcements.