Apple is preparing for a noticeable shift in the physical design of its next flagship smartphone, and the change matters because it affects how the device feels in your hand and whether it fits in your pocket. A new leak suggests the upcoming iPhone 18 Pro will be significantly thicker than its predecessor, a departure from the industry's long trend toward slimmer devices. This potential increase in bulk likely signals internal changes that buyers should watch closely before making a decision.
Leak suggests thicker design and larger battery for September launch
The hardware in question centers on the iPhone 18 Pro and its larger sibling, the iPhone 18 Pro Max. Apple is expected to launch both models in September, continuing its annual release cycle. The company will retain the aluminum alloy mid-frame introduced with the iPhone 17 Pro, opting for this material over titanium again. This structural choice remains consistent with recent design language while accommodating new internal components.
Spec comparison
| Spec | iPhone 18 Pro | iPhone 18 Pro Max |
|---|---|---|
| Thickness | 9.9mm to 10.9mm | Not specified |
| Battery (SIM) | 4,056mAh | 5,391mAh |
| Battery (US eSIM) | 4,288mAh | 5,567mAh |
| Mid-frame Material | Aluminum alloy | Aluminum alloy |
The most striking detail in the leak concerns the device's thickness. The leaker estimates the iPhone 18 Pro will measure between 9.9mm and 10.9mm thick, which is a substantial jump from the 8.75mm measurement on the iPhone 17 Pro. The source described this final thickness figure as one that will be "somewhat surprising." This increase is reportedly driven by Apple's plan to introduce the iPhone's first variable aperture lens, which requires more physical space.
Battery capacity is also increasing across the board, with China 3C certification confirming larger cells for both models. The SIM-card version of the iPhone 18 Pro is listed with a 4,056mAh battery, up from 3,988mAh in the iPhone 17 Pro. The eSIM-only version sold in the US moves from 4,252mAh to 4,288mAh. The Pro Max sees even larger gains, with its SIM-card model rising to 5,391mAh from 4,823mAh, and the US eSIM variant jumping to 5,567mAh from 5,088mAh. We've been tracking iPhone 18 Pro closely — see our earlier coverage on iPhone 18 Pro Cases Leak Reveals.
Apple has not officially confirmed these specifications, and the thickness figures remain unverified rumors from Weibo leaker Digital Chat Station. However, the battery capacity data comes from official certification filings, providing a solid baseline for the expected hardware improvements. The combination of a larger battery and a new camera lens explains the physical expansion, even if the exact final dimensions are still subject to change before the September launch.
Source: NotebookCheck
