A Guide to Cleaning and Speeding up Your Slow Mac

Last modified
Wednesday, December 30, 2020
Member of the AppleVis Editorial Team


If you’re a Mac Voiceover user, there’s one word you absolutely hate hearing, the B word.

Of course, I’m talking about the word, “Busy.” It may pass after a few seconds, causing only minor annoyance, or it can happen frequently and significantly disrupt your workflow.

Often times, repeated experiences like this mean you probably have some performance issues to address. In this guide, I will give an overview of some of the most common problems and solutions. That being said, a slow Mac is a nonspecific symptom with many possible causes; so there might be other explanations for your problem.


If you’re a Voiceover user, you’re probably accustom to hearing the word, “Busy,” spoken at various points and not being able to navigate normally. This phenomenon describes intense processor activity that limits your ability to navigate within the focused app, and in extreme cases, your entire system.

Visually, this is conveyed by a spinning beachball, affectionately known as the, “Spinning beachball of death,” or, “pinwheel of death.” Therefore, if you are seeking help from a sighted user, describe the problem as something like, “I’m getting the beachball,” or, “It’s beachballing.” Likewise if you are helping a sighted user who describes a problem this way, you know it is the same as if a Voiceover user says, “It’s going busy.” In formal terms, an app that exhibits this behavior is said to be unresponsive.

When completing a processor or graphics intensive task, such as media editing or complex video rendering, this is normal. However, if it happens during basic tasks such as word processing, file management, or simple web browsing, you likely have some underlying problem, either software or hardware related. You will find solutions to some of the software problems in this guide, but keep in mind that there is a multitude of possible problems and individual use cases to consider, making discussion of every possible diagnosis impossible.

If you believe your problem is hardware related, you should backup your data and take your Mac into a professional for service. For information on backing up with Time Machine, the Mac's built-in backup utility, check out this guide.

Storage? Memory? Ram?

In this guide, I will refer to memory or ram, which is confusingly enough, different from storage.

Storage, as the name implies, refers to the capacity of media such as a hard drive or solid-state drive to store data. Memory, or ram, refers to your computer’s capacity to multitask. Therefore, in a nutshell, the more ram your computer has, the more apps it can run at once.

Some quick tips for busy apps

If an app you’re using has gone busy for no apparent reason, the first thing to try is to Command-Tab away from it, wait for Voiceover to announce that the app in question is ready, then Command-Tab back to it. If that doesn’t work, Command-Tab away from the app and turn Voiceover off, wait a few seconds, then turn it on again.

Finally, if all else fails, force quit the app by Command-Tabbing to it and pressing Command-Shift-Option-Escape, or Command-Shift-Option-Function-Tab if you're Mac's keyboard doesn't have an Escape key. Alternatively, you can press Command-Option-Escape, or Command-Option-Function-Tab if you're Mac's keyboard doesn't have an Escape key, to open the force quit window and select the problem app from the table. Command Option Escape is the closest thing to Control-Alt-Delete on Windows.

If one app does this consistently, it’s possible the app doesn’t work well with Voiceover or your version of macOS, or has some other bug that substantially affects its performance.

On the other hand, if the issue spreads to the point that your computer has gone completely unresponsive, there is likely a deeper problem with your system. If such a problem occurs, first try pressing and holding the power button for about a second, and clicking restart in the resulting dialog. If that doesn’t work, perform a force shutdown by pressing and holding the power button for about ten-seconds then pressing it again to turn the computer back on.

Important: if you force shutdown your computer, you’ll lose any unsaved work, so do this only as a last resort.

Third-party maintenance utilities

While usually not requiring the same level of maintenance that Windows does to stay healthy, there are a few things you can do periodically to maximize your Mac’s performance. Generally, there are two approaches to completing these tasks; either manually or with the help of third-party maintenance utilities.

In my experience, I don’t need to conduct Mac maintenance very often, so I find I can get away without third-party software. If my internal disk get’s full, one of the leading causes of slowdowns, I can get away with manually deleting old and unnecessary files. Likewise, many other common problems can be resolved using the Terminal app to issue commands directly to the OS.

However, if you are having problems and don’t feel comfortable manually cleaning or working with the command line, you may benefit from third-party software. The app I recommend is Onyx, by Titanium Software. This free and accessible utility includes tools that can speed up and resolve problems with your Mac. It also allows you to configure macOS settings and parameters that may not be visible or easy to accomplish manually.

If you’re looking specifically for an app that will remove leftover files from previously installed apps, I would recommend AppCleaner. This free and accessible app displays a list of installed apps and allows you to delete them along with their associated support files, and can also be configured to trigger any time you move an app to the trash.

Whichever method you use for maintaining your Mac, it is important to update your software so you have the latest patches, and to backup your data so you have it in the unlikely event that something goes wrong.

Manual tasks

If you decide to go the manual route, here are some things to get you started.

Checking system resource usage

If specific apps are persistently slowing down your Mac, you can see how much of the CPU and ram they’re using, as well as their impact on energy usage and disk and network activity.

Open Activity Monitor, located in the Utilities folder, or find it with Spotlight or Siri. Select what you want to view in the, “Segmented control,” radio group in the toolbar, such as CPU or memory. The table to the right of the toolbar shows a list of processes, with the most taxing ones on top. You can quit processes to make more of the CPU or ram available, but only quit them if you know what they are.

If an app you need is using a disproportionate amount of system resources, try reinstalling it or contact the developer with your findings.

Decluttering your desktop

While it is convenient to drop your most used files on the desktop, the desktop process is constantly running. The more files that are there, the more ram is needed to retain the window, subtracting from what would be available to complete user tasks.

Therefore, if you have a lot of files on the desktop, it is a good idea to organize them into a couple of folders.

Optimizing storage

As mentioned earlier, a lack of available disk space can be a leading cause of slower than expected performance. To make the best use of your Mac’s internal storage, macOS includes tools that let you store files remotely in order to save space locally, as well as other options to delete unnecessary files.

To view recommendations and set options, choose Apple > About this Mac, and select the, “Storage,” radio button in the toolbar. In the scroll area, click the, “Manage,” button next to your startup disk, usually called Macintosh HD. The resulting dialog shows a table with options to store files in iCloud, remove watched movies and tv shows, review and remove space intensive apps and resources, and automatically remove items from the trash after thirty days.

You can also view large files, as well as the contents of your Downloads folder or any other folder where files could accumulate.

When you store files in iCloud, they will still appear in the Finder as normal. Pressing Command-O or a similar action to open that file will cause it to download to your computer where you can work with it as normal. Files that you haven’t opened recently will be offloaded to iCloud. More information about iCloud can be found in this guide.

Manually locating large files

In addition to viewing large files in the storage settings discussed in the previous section, you can manually search for large files using Spotlight. If you have large files that you no longer need, you should delete them to save space.

To locate large files in the Finder, follow these steps.

  1. Press Command-Option-Space to open the full search window.
  2. Change the criteria popup menu to other, and choose file size from the resulting table. Tip: you can press the letter F in the table to jump down to the, “File size,” option. If there is no popup menu in the window, click the, “Hide search criteria,” toggle button to reveal it.
  3. Specify your search criteria. For example, you could search for files larger than one gigabyte.

The search results should show all the files matching the criteria you defined. Delete any files you don’t need, empty the trash, and restart the computer.

Verifying your disk

If your Mac is persistently unresponsive, E.G. various apps inexplicably go busy when doing basic tasks or nothing at all, you may have a problem with your internal disk. If it is a problem with the integrity of the file system, it can usually be repaired with Disk Utility or in some cases, by reinstalling macOS. However, if your disk is physically failing, you should take your Mac to a professional for service.

To assess the health of your disk, follow these steps.

  1. Open Disk Utility, located in the Utilities folder, or find it with Spotlight or Siri.
  2. Select your disk, usually called Macintosh HD, in the table, and click the first aid button in the toolbar. During verification, your computer will become unresponsive and there will be no Voiceover feedback; this is normal and should resolve when verification is complete.
  3. Repeat the process for the Macintosh HD - data, volume, typically located just below Macintosh HD in the table.
  4. If Disk Utility reports problems with either volume that it cannot repair automatically, start up your Mac while holding down Command-R, and run first aid from Disk Utility in macOS recovery.

Note: for this to work, you'll need either a built-in keyboard or a USB keyboard connected to your Mac. Also, in this mode, you must turn Voiceover on manually; it doesn’t respect your user settings. The only voice in this mode is Fred, which cannot be changed.

Clearing browser data

Over time, data from your web browser, such as history, caches and cookies can accumulate, occupying valuable storage space and potentially degrading performance. Therefore, it is a good idea to periodically clear this data.

To clear website data in Safari, choose Safari > clear history.

To clear cookies while keeping history intact, choose Safari > Preferences, or press Command Comma, and click the privacy button in the toolbar. Click manage website data, and in the resulting dialog, select the individual cookies you want to remove, or click remove all to remove all cookies. Clearing cookies will sign you out of any websites you were previously signed into and which remember your computer when you visit them.

Clearing caches and logs

Like browser data, caches and log files from macOS and your installed apps can accumulate, which have the potential to become corrupted and degrade performance. To clear this data, follow these steps.

  1. In the Finder, press Command-Shift-G or choose Go > go to folder.
  2. In the resulting dialog, type or copy and paste the following path. ~/library
  3. Your user Library folder should open. Open the caches folder, select all the files in it, and move them to the trash. Important: only delete the files in this folder, not the folder itself.
  4. Go back to the Library folder and open the logs folder. Repeat the process, select and delete everything in that folder.
  5. Press Command-Shift-G or choose go > go to folder.
  6. In the resulting dialog, type or copy and paste the following path. /library
  7. The library folder at the root of your startup disk should open. Repeat the process for the caches and logs folders in this location. Note: in the Library folder at the root of your startup disk, you’ll be prompted to authenticate to delete files, as these are system rather than user files.

While you’re in the library folders, you can look for leftover files from apps you may have uninstalled. These files are found most commonly in the, "Application Support," and, "Preferences," folders, although it is not uncommon to find small files spread throughout the Library folders.

Caution: the library folder’s contain essential files needed for macOS to function. Therefore, only delete files if you know what they are and know you don’t need them. When you’re done, restart the computer and empty the trash.


This guide contains a number of possible solutions I am aware of to clean and speed up your Mac. If you believe any of the information in this guide is inaccurate, or if you know of other tips and tricks, sound off in the comments.

More help is available in your Mac’s built in help, Apple support and the AppleVis forum to name just a few good sources.


The article on this page has generously been submitted by a member of the AppleVis community. As AppleVis is a community-powered website, we make no guarantee, either express or implied, of the accuracy or completeness of the information.



Submitted by PaulMartz on Saturday, November 28, 2020

Member of the AppleVis Blog Team

Great article.

In About This Mac > Storage, there is a visual Usage graph so sighted users can see their usage at a glance. Blind users can interact with this and examine each value with VoiceOver, and when I do so, I find a category called "Other" that is consuming 79GB. Any idea how to examine this further or clear it out?

Submitted by Chris on Sunday, November 29, 2020

Ah yes, the extremely irritating other category. It's also present on iOS and extremely difficult to deal with. I believe this category contains caches, logs, and other system data. I don't know of a way to completely get rid of this garbage without erasing your disk and installing a new copy of macOS.

Even if this is done, the other category will start increasing in size as you use the system. If you don't want to do a clean install, try using Onyx and/or periodically clean out the caches and logs folders in your user Library folder and the Library folder under Macintosh HD. Having said all that, you may want to perform a clean install at least once every year or two. Your computer will be faster and you'll have more free storage.

Submitted by PaulMartz on Sunday, November 29, 2020

Member of the AppleVis Blog Team

In reply to by Chris

I couldn't find Onyx in the App Store. I did find something called OS Cleaner. Is that the same app?

I found a folder with 25GB in my Documents folder. I hadn't touched it in years, so I moved it out to an external storage device. Strangely enough, this reduced the size of my Other category. I would've thought that would've been in the Documents category, because that's where the folder resided on disk.

Yes I have some experience with the Other category on the iPhone. I've cleared it out before in the manner similar to what you describe: One, do a full backup. Two, do a full reset on the phone. And three, restore from backup.

The category is certainly a mystery, whether it's on the phone or a Mac.

Submitted by Tyler on Sunday, November 29, 2020

Member of the AppleVis Editorial Team

In reply to by PaulMartz

To my knowledge, Onyx is not available in the Mac AppStore, only from the developer's website which is linked in the article. However, I do not believe the current version of this utility has been tested with macOS Big Sur, and thus its use is not recommended until a new version is released.

I have not used OS Cleaner, so cannot comment on the usefulness or accessibility of that app.

Submitted by Skippy on Monday, November 30, 2020


If you attempt to do something in disk utility, through recovery mode, using voice over. Voiceover will crash, when you interact with the table.
This bug began with the latest version of macOS, which is Big Sur.