Do live wallpapers drain your Mac's battery?
A live wallpaper uses some power, because something has to keep drawing it. How much depends on how it is made. A video has to be decoded for as long as it plays, while a generated wallpaper only has to draw the frames it needs, and it can stop when nobody can see it.
What costs power
Two things matter: how many frames are drawn each second, and how much work each one takes. Most of the CPU cost is the same for every frame, whatever is in it, because the Mac has to prepare the frame and hand it to the screen. So the biggest saving is not drawing frames nobody needs.
A slow wallpaper barely changes from one frame to the next. Running it at 60 or 120 frames a second spends power on differences you cannot see.
What we measured
Pixel Soup 1.2 picks its frame rate from the wallpaper's speed. These are the CPU figures we measured on an Apple silicon MacBook Pro, as a share of one CPU core, with the wallpaper visible:
| Speed setting | Frames a second | CPU |
|---|---|---|
| 0.6 and above | 30 | 1.1% |
| 0.2 to 0.6 (the default is 0.35) | 20 | 0.8% |
| 0.06 to 0.2 | 15 | 0.6% |
| 0.02 to 0.06 | 10 | 0.4% |
| Below 0.02 | 5 | 0.2% |
These come from one test on one Mac, using a small wallpaper window, so treat them as a guide. Your numbers will depend on your Mac, your displays and the wallpaper. The GPU does work as well, and this table does not count that.
How to check any wallpaper app
- Open Activity Monitor from Applications, then Utilities.
- On the CPU tab, find the wallpaper app and watch its % CPU for a minute, with your desktop showing.
- On the Energy tab, compare its Energy Impact against your other apps.
- Cover the desktop with a window and watch again. A good wallpaper app should fall to almost nothing.
Remember to check the desktop is actually visible while you measure, or the number will look better than it really is.
How to use less
- Slow it down. In Pixel Soup, Speed goes down to 0.01, which changes so gently you stop noticing it and draws just 5 frames a second.
- Use a still. A still wallpaper is an ordinary desktop picture and costs nothing once it is set.
- Keep windows maximised. Pixel Soup stops drawing when windows cover the whole desktop.
A live wallpaper on a Mac does not have to be a video. If you are comparing apps, we looked at seven in the best live wallpaper apps for Mac.
Get Pixel Soup, $4.99 Once, no subscription. Also on the Mac App Store.