To stop your MacBook display from dimming on battery, choose Apple menu › System Settings › Battery, click Options, and turn off “Slightly dim the display on battery.” Your screen then stays at the same brightness when you unplug the charger.
This guide covers that setting, where it lives in older versions of macOS, and the other settings that can make a MacBook screen darker, such as auto-brightness, Low Power Mode and inactivity timers. The steps follow Apple’s guide to Battery settings on a Mac laptop and apply to MacBook Air and MacBook Pro models running macOS Ventura or later.
How to Stop the MacBook Display From Dimming on Battery
- Choose Apple menu › System Settings.
- Click Battery in the sidebar. You may need to scroll down.
- Click Options at the bottom of the Battery pane. Apple’s guide lists these settings under Additional Options.
- Turn off Slightly dim the display on battery.
- Click Done if a Done button appears.
Result: The next time you unplug your MacBook, the brightness stays where you set it instead of dropping a notch.
Apple describes this option as a way to conserve energy by dimming the display when the Mac isn’t plugged in, so expect somewhat shorter battery life with it turned off.
On older versions of macOS
- macOS Monterey or Big Sur: open System Preferences › Battery and uncheck “Slightly dim the display while on battery power.”
- macOS Catalina or earlier: open System Preferences › Energy Saver › Battery and uncheck the same option.
Some early versions of System Settings placed the switch under Displays › Advanced, so check there if you don’t see it in Battery.
Why Is My MacBook Screen Still Dimming?
If the screen still gets darker after you turn off the battery dimming option, one of these settings is usually responsible.
Automatic brightness
Macs with an ambient light sensor can adjust brightness based on the light around you, plugged in or not. To turn it off, choose Apple menu › System Settings, click Displays, and turn off Automatically adjust brightness. Then drag the Brightness slider to the level you want.
Result: Brightness only changes when you change it. Apple notes in its display brightness guide that turning off auto-brightness may affect battery life and energy use.
Low Power Mode
In Battery settings, Low Power Mode (or the Energy Mode menu on some models) reduces energy use to stretch battery life. It may also keep the screen dimmer than usual, so set it to Never or Automatic if you want full brightness on battery.
The display turns off when you’re idle
If the screen dims and then goes dark while you’re reading, it’s the inactivity timer rather than the battery setting. Choose Apple menu › System Settings › Lock Screen and choose a longer time for Turn display off on battery when inactive. Apple’s Lock Screen settings guide lists a separate timer for when you’re plugged in.
Is It Bad to Turn Off Battery Dimming?
No. It doesn’t harm the battery or the display. The only trade-off is battery life: a brighter screen uses more power, so your MacBook won’t last as long on a charge. If you only need full brightness sometimes, such as for photo editing or working outside, leave the setting on and press the brightness key to raise it when you need to.
Frequently Asked Questions
Why does my MacBook get dimmer when I unplug it?
Because “Slightly dim the display on battery” is turned on by default to save power. Turning it off in Battery › Options stops it.
Does this setting exist on a Mac desktop?
No. It’s a laptop battery option. Desktop Macs use Energy settings instead.
More Mac Guides
- How to choose when the screen saver turns on
- How to change the screen resolution on a MacBook Air
- How to add the volume control to the Mac menu bar
For movie nights, you can also connect a 2012 MacBook Air to an HDTV.
Matthew Burleigh has been writing tech tutorials since 2008. His writing has appeared on dozens of different websites and been read hundreds of millions of times.
After receiving his Bachelor’s and Master’s degrees in Computer Science he spent several years working in IT management for small businesses. However, he now works full time writing content online and creating websites.
His main writing topics include iPhones, Microsoft Office, Google Apps, Android, and Photoshop, but he has also written about many other tech topics as well.