The iPhone 18 Pro Max this year, in addition to a camera system with variable aperture and the new A20 Pro chip, received a significant upgrade in the battery department.
According to ITNA quoting Phonearena, the battery capacity of this phone has increased by about 10 percent compared to the previous generation and for the first time is larger than the battery capacity of some Android rivals such as the Galaxy S26 Ultra and Pixel 11 Pro XL. The global version of the iPhone 18 Pro Max in this test was equipped with a 5391 mAh battery.
To evaluate real battery performance, a YouTube video playback test was conducted on four phones: the iPhone 18 Pro Max, iPhone 17 Pro Max, Galaxy S26 Ultra and Pixel 11 Pro XL. Screen brightness was set to the same level, all phones were tested with 100 percent battery and full battery health, and the devices were connected to the same Wi‑Fi network.
After five hours of continuous video playback, the iPhone 18 Pro Max took first place with 61 percent charge remaining. The Pixel 11 Pro XL was next with 57 percent, and the Galaxy S26 Ultra performed worse with 50 percent charge remaining. The iPhone 17 Pro Max ended the test with 48 percent charge.
In the seven‑hour test, the iPhone 18 Pro Max still maintained its lead with 42 percent charge. That figure was 37 percent for the Pixel 11 Pro XL, 27 percent for the Galaxy S26 Ultra, and only 22 percent for the iPhone 17 Pro Max.
These results indicate that the increased battery capacity alongside the higher efficiency of the A20 Pro chip can have a significant impact on the real-world battery life of the iPhone 18 Pro Max. The test also shows that battery capacity alone is not a suitable metric to predict a phone’s battery life and that chip and software optimization play an important role.