[razh]

There's more detail in the iPhone battery information page.

Testing conducted by Apple in August 2021 using preproduction iPhone 13 mini, iPhone 13, iPhone 13 Pro, and iPhone 13 Pro Max units and software, subscribed to LTE and 5G carrier networks. Video playback consisted of a repeated 2-hour 23-minute movie purchased from the iTunes Store, tested with stereo audio output. Video playback (streamed) consisted of a repeated 3-hour 1-minute HDR movie purchased from the iTunes Store, tested with stereo audio output. All settings were default except: Bluetooth was paired with headphones; Wi-Fi was associated with a network; the Wi-Fi feature Ask to Join Networks, Auto-Brightness, and True Tone were turned off.

https://www.apple.com/iphone/battery.html#:~:text=Video%20Pl...