Auto-Brightness adjusts an iPhone’s display brightness based on ambient light. On the iPhone 7, Apple moved this control between different Settings locations across iOS versions, so older screenshots may not match the software currently installed on the phone.
Turn off Auto-Brightness
- Open Settings.
- Select Accessibility. On older iOS versions, start under General > Accessibility.
- Open Display & Text Size when that menu is available.
- Scroll to Auto-Brightness.
- Turn the switch off.
Set brightness manually afterward
Open Control Center and drag the brightness slider to the level you prefer, or use the Display & Brightness settings. With Auto-Brightness disabled, the iPhone will not make the same automatic ambient-light adjustments.
Turning it off can affect battery life
A screen kept brighter than necessary uses more power. Apple generally recommends leaving Auto-Brightness enabled because it can improve viewing comfort and help reduce unnecessary display power use.
Other features can still change how the screen looks
True Tone on supported devices, Night Shift, Reduce White Point, Low Power Mode, and accessibility display settings can affect perceived brightness or color. The iPhone 7 does not support every display feature found on newer models, but Auto-Brightness is not the only setting that can influence appearance.
If brightness changes dramatically even with Auto-Brightness off, check whether the iPhone is overheating. iOS can reduce display brightness temporarily to protect the device. The iPhone 7 is also a legacy model that cannot run current iOS releases, so consider a supported device for ongoing security-sensitive use.
For extra dimming, see reducing bright colours with Reduce White Point.
Kermit Matthews is a freelance writer based in Philadelphia, Pennsylvania with more than a decade of experience writing technology guides. He has a Bachelor’s and Master’s degree in Computer Science and has spent much of his professional career in IT management.
He specializes in writing content about iPhones, Android devices, Microsoft Office, and many other popular applications and devices.