The quickest way to change your desktop background

Open System Settings, click Wallpaper in the left sidebar, then select Desktop. Choose a built-in image or click Add to upload your own photo. That's it — the change takes effect when ready.

If System Settings doesn't open, click the Apple menu in the top-left corner of your screen, then select System Settings. On older Macs running Big Sur or earlier, the setting lives in System Preferences instead, and the sidebar option is called Desktop & Screen Saver.

Key Takeaways

  • Open System Settings, find Wallpaper in the sidebar, and select Desktop to see all available background options.
  • You can use any photo on your Mac as a background by clicking Add and choosing the file from your computer.
  • macOS comes with dozens of built-in wallpapers organized by category — Dynamic, Light, Dark, and Collections.
  • The background change happens when ready and applies only to your user account, not to other people who log into the same Mac.

Using a photo from your own files

Click the Add button (the plus sign) at the bottom of the Wallpaper window. A file browser opens. Navigate to the folder where your photo lives — usually Pictures, Downloads, or Desktop — and select the image you want.

macOS accepts most common photo formats: JPEG, PNG, HEIF, and TIFF all work. Once you select the photo, it appears in the Wallpaper list and becomes your desktop background right away. You can delete it from this list later without deleting the original file from your Mac.

Understanding the built-in wallpaper categories

The Dynamic wallpapers change throughout the day based on the time of sunrise and sunset in your location. Light wallpapers stay bright all day. Dark wallpapers stay dark. Collections group images by theme — Aerial shows video footage from around the world, Nature shows landscapes, and so on.

If you want a different look depending on the time of day, choose a Dynamic wallpaper. If you prefer one consistent image, pick from Light, Dark, or any Collection. You can also set different backgrounds for different spaces if you use multiple desktops — each space remembers its own choice.

What to do if your photo looks stretched or cut off

After you select a photo, look for the dropdown menu below the preview that says "Fill screen" or "Fit to screen." Fill screen stretches the image to cover the whole background, which may crop the edges. Fit to screen shrinks the image to show the whole thing, which may leave empty space around it.

Choose whichever matches what you want to see. If the photo is very small or very large compared to your screen, one option will look better than the other. You can change this setting anytime without re-selecting the photo.

Changing the background for your lock screen separately

Your lock screen — the image you see before you type your password — can be different from your desktop background. In System Settings, click Wallpaper, then select Lock Screen instead of Desktop. The process is identical: choose a built-in image or add your own photo.

This is useful if you want a professional image on your lock screen but something personal on your desktop, or vice versa. The two settings are completely separate, so changing one does not affect the other.

Why your background reverts after restart

If you set a background and it changes back to the default after you restart your Mac, the photo file may have been moved or deleted. When you choose Add and select a photo, macOS remembers the location of that file, not a copy of the image itself. If you move the photo to a different folder or delete it, the Mac can't find it anymore and falls back to a default wallpaper.

To prevent this, keep your chosen photo in a permanent location — like Pictures or a dedicated Wallpapers folder — and don't move it. If you want to organize your photos later, move them before you set them as your background, or use a built-in wallpaper instead.

Frequently Asked Questions

Can I use a video as my desktop background?

No. macOS only supports still images for the desktop background. The Dynamic wallpapers that appear to move are actually a series of still images that change throughout the day, not video files. If you want moving imagery, you can use a screensaver instead, which plays when your Mac is idle.

Will changing my background affect other people who use this Mac?

No. Each user account on a Mac has its own desktop background setting. If you share your Mac with family or roommates, they can each set their own background, and it will only show when they log in. Your background stays the same when you log back in.

What if I can't find the Wallpaper option in System Settings?

If you're using macOS Big Sur or earlier, the setting is called Desktop & Screen Saver instead of Wallpaper, and it's in System Preferences rather than System Settings. The steps are the same once you find it. On newer Macs, make sure you're looking in the left sidebar — Wallpaper should be near the top of the list.

Can I set a different background for each space or virtual desktop?

Yes. If you use multiple spaces (created by swiping up with four fingers on your trackpad), you can set a different background for each one. Switch to the space you want, open System Settings, and choose a background. That background applies only to that space. Other spaces keep their own backgrounds.