The iPhone 13 can adjust its screen brightness automatically as the light around you changes. Apple calls this feature Auto-Brightness. On current versions of iOS, its switch is in Accessibility settings rather than on the main Display & Brightness screen.
How to Turn Auto-Brightness On or Off on an iPhone 13
- Open Settings.
- Tap Accessibility.
- Tap Display & Text Size.
- Scroll to Auto-Brightness.
- Tap the Auto-Brightness switch to turn the feature on or off.
When Auto-Brightness is enabled, your iPhone uses its ambient-light sensor to raise or lower the display brightness for the environment. You can still make a temporary brightness adjustment from Control Center.
How to Adjust Brightness Manually
- Swipe down from the top-right corner of the iPhone 13 screen to open Control Center.
- Drag the brightness slider up for a brighter screen or down for a dimmer one.
You can also go to Settings > Display & Brightness and move the Brightness slider there.
Why Does the Screen Brightness Still Change?
Turning off Auto-Brightness does not guarantee that the display will remain at exactly the same apparent brightness in every situation. Other iPhone features can affect how the screen looks.
True Tone changes the color and intensity of the display to suit ambient lighting. Night Shift makes the display warmer on a schedule. Low Power Mode can change some display behavior to save energy. The iPhone may also temporarily reduce maximum screen brightness when the device becomes too warm.
If the screen looks dim even with the brightness slider high, check Settings > Display & Brightness for True Tone and Night Shift, and allow an unusually warm iPhone to cool down.
Should You Leave Auto-Brightness Enabled?
For most people, yes. Auto-Brightness makes the screen easier to see as lighting changes and can help avoid using more display brightness than necessary. Apple also notes in iOS that leaving the feature off can affect battery life and long-term display performance.
Turning it off can still make sense when you need consistent brightness for a particular task, such as comparing images under controlled lighting. You can turn it back on at any time using the same Accessibility menu.
Matt Jacobs has been working as an IT consultant for small businesses since receiving his Master’s degree in 2003. While he still does some consulting work, his primary focus now is on creating technology support content for SupportYourTech.com.
His work can be found on many websites and focuses on topics such as Microsoft Office, Apple devices, Android devices, Photoshop, and more.