Apple has revealed the exact battery capacity inside iPhone Duo, confirming that its first foldable iPhone uses a combined 4,883mAh dual-battery system.
The figure appears in Apple’s official European product information for iPhone Duo, which lists a rated battery capacity of 4,883mAh for model A3720.
That confirms earlier leaks suggesting Apple had split the battery across two cells, one on each side of the foldable design. Apple describes the setup as an iPhone-first dual-battery system, with software managing both batteries as a single power source.
The number also gives buyers a clearer idea of where iPhone Duo sits compared with Apple’s other flagship models. For context, iPhone 18 Pro has a smaller battery, while iPhone 18 Pro Max has a larger one, reflecting the different internal layouts and physical sizes of each device.
Apple has already published its own battery-life estimates for iPhone Duo. The company rates the device for up to 24 hours of typical use, while video playback can reach up to 44 hours when using the smaller outer display or up to 31 hours when using the larger inner display.
The Apple Post previously broke down how iPhone Duo battery life changes depending on which screen you use, with the 7.6-inch inner display naturally drawing more power than the 5.4-inch outer screen.
The foldable design plays a major role in how Apple has packaged the battery. Apple says one high-energy battery is positioned on each side of iPhone Duo, helping maximize capacity inside a device that also has to accommodate its hinge, two displays and unusually thin unfolded body.
Apple also made iPhone Duo eSIM-only worldwide, saying the removal of physical SIM hardware creates additional internal room for battery capacity. The device supports fast wired charging to around 50 percent in approximately 20 minutes with a compatible 60W-capable or higher adapter, while MagSafe and Qi2 can reach around 50 percent in roughly 30 minutes with appropriate charging equipment.
iPhone Duo officially launches on October 23, with prices starting at $1,999 in the United States and £1,999 in the United Kingdom.
