Mac slow after a macOS update? What’s normal

Why is my Mac slow after an update?

After you install a software update or upgrade, Spotlight indexes your Mac again, so search can find your files, mail and other data. Apple says indexing also happens when you first set up a Mac and as your data changes. This work runs in the background. Apple lists Spotlight indexing after you move your data to a new Mac among the heavy tasks that make the fans speed up, and says fan noise during work like this is normal.

How long does a Mac stay slow after an update?

Until macOS’s background work is done. Apple says Spotlight indexing can take hours or even days, depending on how much data is on your Mac. Later updates to the index are much faster. Indexing finishes sooner when your Mac is:

• not in use;
• connected to power;
• connected to the internet over Wi-Fi or Ethernet, so mail and other data can download to be indexed.

To see whether it’s still running:

1. Press Command–Space bar to open Spotlight.
2. Look at the top of the Spotlight window. While indexing is still running, an indexing progress indicator shows there.

The simplest fix is time: plug in your Mac and leave it be while you take a break.

Is it the update, or one of your apps?

Activity Monitor shows whether one of your apps or macOS itself is doing the work.

1. Open Activity Monitor: press Command–Space bar, type Activity Monitor, then press Return.
2. Click CPU, then click the % CPU column heading to sort the list, busiest first.
3. Watch the top of the list for a minute. An app that stays there for minutes, not seconds, is doing sustained work.

4. Read System and User at the bottom of the window. Apple defines System as the share of the processor used by processes that belong to macOS, and User as the share used by apps you opened and the processes they opened.

Here is how to read the two:

Activity Monitor counts each processor core as 100%, so Blender’s 978.6% keeps almost ten of this Mac’s 15 cores busy. How to check CPU usage on a Mac explains every number on that tab.

Do my apps need updating?

Check for app updates after a macOS update.

1. Open the App Store.
2. Click Updates in the sidebar.
3. Click Update beside each app, or click Update All.

To have apps update on their own, choose App Store > Settings, then select Automatic Updates. For apps from outside the App Store, check with each app’s developer. Apple also suggests quitting any app that isn’t compatible with your Mac, such as one that needs a different processor or graphics card. To see whether another macOS update is waiting, choose Apple menu > System Settings, click General, then click Software Update.

Are login items slowing it down?

Apps that open at login start every time you log in, and some keep working in the background.

1. Choose Apple menu > System Settings, click General, then click Login Items & Extensions.
2. Under Open at Login, select an app you don’t need at login.
3. Click the Remove button (−).

How to stop apps opening at startup on a Mac covers the background items too.

Is there enough free space?

A startup disk without enough free space can slow a Mac down, and installing a macOS update needs room of its own.

1. Choose Apple menu > System Settings, click General in the sidebar, then click Storage.
2. Read the line at the top: how much of the disk is used.
3. If it’s nearly full, try the recommendations, move large files you want to keep to an external drive, and empty the Trash.

If an update won’t install for lack of space, Apple says starting up in safe mode might free enough room, for a while, to finish it.

Does restarting or safe mode help?

Restarting closes every app and starts fresh: choose Apple menu > Restart. Safe mode goes further. It starts your Mac without login items, extensions that macOS doesn’t need and fonts that macOS didn’t install, checks the startup disk and clears some system caches.

• Apple silicon: shut down, then press and hold the power button until you see “Loading startup options” or the Options icon. Select your startup disk, then hold Shift and click Continue in Safe Mode.
• Intel: turn on your Mac and immediately press and hold Shift until the login window appears.

If your Mac is fine in safe mode but slow again after a normal restart, Apple says a login item or other software that safe mode blocks is the likely cause. Spinning wheel on Mac? What it means and what to do covers safe mode and Apple Diagnostics in more detail. If your Mac is still slow once the update has settled, How to speed up a Mac: what actually helps ranks every fix.

Questions people also ask

Why is my fan loud after a macOS update?

Heavy processor work speeds up the fans, and Apple names Spotlight indexing after moving data to a new Mac as one such task. If the fans stay loud for days, check Activity Monitor for an app at the top of the CPU list.

Can I use my Mac while it indexes?

You can, but Apple says indexing finishes faster when your Mac isn’t in use.

Does every Mac do this after an update?

Yes. Apple says Spotlight indexes after you install a software update or upgrade, and how long it takes depends on how much data is on the device.