The fastest way to change your background

On Windows, right-click any empty space on your desktop, select Personalize, then click Background in the left menu. Choose Picture from the dropdown, then click Browse to pick an image from your computer. On Mac, open System Settings, go to Wallpaper, click the + button, and select an image file.

Both systems come with built-in images you can use without finding your own. Windows stores these in the Background section under Recent or Suggested. Mac shows them in the Wallpaper tab organized by category — click any thumbnail to apply it instantly.

Key Takeaways

  • Windows: right-click the desktop, select Personalize, choose Background, then pick Picture and browse for your image.
  • Mac: open System Settings, go to Wallpaper, click the plus button, and select an image file from your computer.
  • Both operating systems include free built-in images you can use without downloading anything.
  • You can set different backgrounds for each monitor if you use multiple screens on Windows.
  • Image files must be in a common format like JPG, PNG, or BMP to work as a background.

Finding images on your computer to use

Your computer already has images stored in several places. On Windows, check your Pictures folder — this is where most downloaded or saved images end up. On Mac, the Pictures folder serves the same purpose. Both systems also store screenshots in dedicated folders: Windows saves them in Pictures > Screenshots, and Mac saves them to the Desktop or a Screenshots folder depending on your settings.

If you have taken photos with a phone or camera, look for a folder named after the device or a sync service like OneDrive (Windows) or iCloud (Mac). These folders often contain photos organized by date. You can use any of these images as your background — the system does not care where the file lives, only that you can find it.

Using images from the internet

When you find an image online that you want to use, right-click it and select Save image as (the exact wording varies by browser). Choose your Pictures folder as the save location. Once saved, follow the steps in the first section to set it as your background.

Before downloading, check that the image is large enough — backgrounds work best at 1920 × 1080 pixels or larger, though your system will stretch or shrink smaller images to fit. If an image looks blurry when you set it as your background, it was probably too small. You can always delete it and try a different one.

Setting different backgrounds on multiple monitors

On Windows, you can assign a different background to each monitor. Open Settings > Personalization > Background, select Picture, then choose your first image. Right-click the image and select Set for monitor 1 (or whichever monitor number you want). Repeat for each monitor with a different image.

Mac does not offer per-monitor backgrounds in the same way — it applies the same wallpaper to all connected displays. If you need different backgrounds on each monitor, you would need third-party software, but this is rarely necessary for everyday use.

Troubleshooting when your background will not change

If you set a background and it does not appear, restart your computer first — sometimes the change does not take effect until you log out and back in. On Windows, make sure you are not using a solid color or slideshow by accident; check the Background dropdown in Settings to confirm Picture is selected.

If the image file itself is the problem, Windows and Mac only recognize certain formats: JPG, PNG, BMP, GIF, and TIFF. If you have an image in a different format like WebP or SVG, you will need to convert it first using free online tools or image software. On Windows, also check that the image file is not corrupted — try opening it in an image viewer like Photos or Paint to confirm it displays correctly.

Changing your lock screen background separately

Your lock screen (the screen you see before you log in) can have a different background from your desktop. On Windows, go to Settings > Personalization > Lock screen, then choose Picture from the dropdown and browse for an image. On Mac, open System Settings > Lock Screen and click the + button to add an image.

This is useful if you want a professional or private image on your lock screen but a more personal one on your desktop. The process is identical to changing your desktop background — you just navigate to a different settings section first.

Using slideshows and dynamic backgrounds

Instead of a single static image, Windows lets you create a slideshow that cycles through multiple images. Go to Settings > Personalization > Background, select Slideshow from the dropdown, then click Browse to choose a folder full of images. You can set how often the image changes — options range from every 1 minute to every 1 day.

Mac offers dynamic wallpapers that change throughout the day, simulating sunrise and sunset. In System Settings > Wallpaper, look for images labeled "Dynamic" and click one to see a preview of how it shifts. These use more battery power on laptops, so consider switching to a static image if you notice your battery draining faster.

Frequently Asked Questions

Can I use a video as my background instead of an image?

Windows 11 supports video backgrounds, but the feature is limited and requires specific setup. You need to use the Microsoft Store app or third-party software. Mac does not support video backgrounds natively. For most users, a slideshow or dynamic wallpaper is a simpler alternative that achieves a similar effect.

What image size works best for a background?

Match your monitor's resolution — 1920 × 1080 is standard for most laptops and desktop monitors. If your image is smaller, it will look blurry or pixelated when stretched. If it is larger, your system will shrink it down. You can check your monitor resolution in Windows Settings under Display or Mac System Settings under Displays.

Will changing my background slow down my computer?

No. A single static background uses almost no system resources. Slideshows and dynamic wallpapers use slightly more power because your system has to load and switch images, but the impact is negligible on modern computers. If you notice slowness, it is almost certainly caused by something else.

Can I go back to the original Windows or Mac background?

Yes. On Windows, open Settings and choose one of the built-in images from the Background section. On Mac, open System Settings and select one of the default wallpapers from the Wallpaper tab. You can always switch back to your custom image later if you change your mind.

Why does my background look different on my laptop than on my monitor?

Different screens have different aspect ratios and resolutions. An image that looks good on a 16:9 widescreen monitor might look stretched or cropped on a 4:3 or ultrawide display. If you use multiple monitors with different sizes, you may need to adjust the image or use the per-monitor background feature on Windows to get the best result on each screen.