iPhone 18 Pro, Pro Max, and iPhone Duo battery life comparison
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Apple has officially unveiled the iPhone 18 Pro, iPhone 18 Pro Max, and iPhone Duo, and battery life is one of the biggest areas of improvement for the new lineup. The Pro models benefit from new battery designs and a more efficient A20 Pro chip, while the iPhone Duo takes a completely different approach with two batteries, one on each side of the foldable.
Apple claims the iPhone 18 Pro Max delivers the biggest battery life increase ever on an iPhone, while the standard Pro also lasts longer than its predecessor. The Duo, meanwhile, can offer very different battery life depending on whether you are using its large inner display or the smaller outer screen.
Of course, we will get a much better idea of how all three perform once they are properly tested in real-world conditions. For now, though, Apple’s official figures give us a good idea of how they compare.
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iPhone 18 Pro, Pro Max, and Duo battery life & battery size compared
| Model | Battery size | Video playback | Typical usage |
|---|---|---|---|
| iPhone 18 Pro | 4,056 mAh | Up to 36 hours | Up to 24 hours |
| iPhone 18 Pro Max | 5,391 mAh | Up to 45 hours | Up to 30 hours |
| iPhone Duo | 5,400 mAh Dual-battery | Up to 31 hours (inner display) Up to 44 hours (outer display) | Up to 24 hours with mixed display use |
The iPhone 18 Pro can deliver up to 36 hours of video playback on eSIM-only models, while the iPhone 18 Pro Max stretches that to an impressive 45 hours. Apple has also introduced a newer usage measurement designed to better represent how people actually use their phones throughout the day. Instead of only playing video continuously, this test includes activities such as messaging, browsing the web, taking photos, gaming, using social apps, streaming content, and navigation.
Under those conditions, Apple says the iPhone 18 Pro Max can last for up to 30 hours on a full charge. The iPhone 18 Pro, on the other hand, reaches up to 24 hours.
The improvement comes from a combination of redesigned batteries, better efficiency from the new 2nm A20 Pro chip, and software optimizations. Apple has also taken advantage of the space normally used by a physical SIM tray in eSIM-only models to fit a larger battery. Because of this, versions of the iPhone 18 Pro and Pro Max that still include a physical SIM tray get around two hours less video playback.
On the other hand, the iPhone Duo is a little more complicated because battery life depends heavily on which display you are using. Apple has fitted its first foldable iPhone with a dual-battery system, placing one battery on each side of the device. iOS manages the two cells as a single battery, while the A20 Pro chip, C2 modem, and eSIM-only design help improve efficiency.
When using the large 7.6-inch inner display, Apple says the iPhone Duo can provide up to 31 hours of video playback. Switch to the smaller 5.4-inch outer display, however, and that figure jumps significantly to 44 hours. That means the Duo can actually get very close to the iPhone 18 Pro Max when you mainly use the outer screen. However, the larger folding display naturally consumes more power, bringing its video playback time below both Pro models.
For mixed everyday usage, with both screens being used about equally, Apple rates the iPhone Duo for up to 24 hours per charge. That puts it on the same level as the iPhone 18 Pro under Apple’s typical-use measurement.
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