Apple’s latest filings with China’s 3C certification authority have uncovered the battery capacities for the iPhone 18 Pro and iPhone 18 Pro Max, showing a modest boost for the Pro and a more substantial jump for the Pro Max. Apple rarely relies on bigger batteries alone-instead, it boosts battery life mainly through chip and display efficiency improvements.
The 3C documents list the Chinese iPhone 18 Pro battery at 4056 mAh, while the U.S. model comes with a slightly larger 4288 mAh pack. By comparison, last year’s iPhone 17 Pro featured 3988 mAh (China) and 4252 mAh (U.S.), so these increases fall within Apple’s typical incremental updates.
- iPhone 18 Pro (China): 4056 mAh
- iPhone 18 Pro (U.S.): 4288 mAh
- iPhone 18 Pro Max (China): 5391 mAh
- iPhone 18 Pro Max (U.S.): 5567 mAh
The Pro Max’s battery sees a more notable upgrade: 5391 mAh for the Chinese unit and 5567 mAh for the American version. That’s roughly a 500 mAh jump over the iPhone 17 Pro Max’s 4823 mAh (China) and 5088 mAh (U.S.). If accurate at the September unveiling, this will mark the largest battery Apple has ever put in an iPhone.
Despite these gains, Apple’s battery sizes still look conservative compared to Chinese rivals. Brands like Xiaomi, OPPO, and OnePlus have already pushed 6000 to 7000 mAh batteries into premium models, often using silicon-carbon battery cells to boost capacity. Apple, by contrast, has relied more on SoC, modem, and iOS-level power optimizations to maximize battery life. That strategy paid off well enough for Apple to top global smartphone revenue charts in the premium segment in 2025, according to Counterpoint Research.
Leaks hint at other iPhone 18 Pro series upgrades: a new A20 Pro chip built on TSMC’s 2nm manufacturing process, a smaller Dynamic Island notch, and a variable aperture main camera on the Pro Max. The camera setup is expected to include three 48-megapixel sensors alongside a periscope-style telephoto lens. Display sizes reportedly remain unchanged at 6.3 inches for the Pro and 6.9 inches for the Pro Max.
These specs may still shift before the official launch in September, especially if Apple adjusts component sourcing for different regions. The bigger question isn’t the raw milliamp-hour numbers but how well Apple pairs these batteries with its new chip and modem. If current leaks hold true, the iPhone 18 Pro Max could narrow the battery life gap with Android flagships-where Apple’s lead has historically come from superior energy efficiency rather than sheer battery capacity.