Warning icon
MacPaw stands with Ukraine. Here’s how you can help our country win with just several clicks.

How to restore Mac run out of application memory

25.5K views
9 min read

How many times have you seen a “your system has run out of application memory” notification on your Mac? Likely more than once, as this is a common problem for Mac, but users are often confused as it seemingly appears from nowhere.

This error is caused by virtual memory being stored on the hard drive, once the standard RAM fills up. The memory management on macOS is pretty robust, as it’s based on Unix, however, it’s not perfect and that’s why you may be getting a message telling you that the system has run out of application memory. Read on to find out what is application memory, what causes this error, and how to fix it.

What does “system has run out of application memory” mean?

Mac’s operating system stores data for active processes in RAM, or random-access memory. If or when space in RAM runs low, macOS begins storing data on the main drive and swapping it between there and RAM as needed. If your Mac’s drive is overloaded already, this is when it’ll send an application memory issue message. Thus, it’s a good idea to keep a portion of your hard drive free, just in case. You should aim to have at least 10% of disk capacity available for ideal Mac performance.

Now that we’ve figured out what is application memory, let’s look at the four main causes of “your system has run out of application memory” error message on your Mac:

  1. Disk space. Running low on disk space when all RAM has been used and macOS is creating swap files, which take up more and more room on the hard drive. That’s when the system will report that the Mac is about to run out of application memory. 
  2. Multitasking. Running several apps simultaneously can lead to “your system has run out of application memory” notification along with a suggestion to close several apps. 
  3. Browser lagging. Having lots of tabs open or installing numerous extensions may lead to issues in application memory Mac. Be aware that even if these extensions are not being used, they are running with the browser and taking up precious memory space.
  4. Misbehaving apps. Apps do take quite a bit of space, but some apps can be “hogging” memory. Users have reported seeing Mail, Firefox, and Final Cut Pro take up not megabytes, but gigabytes of application memory Mac.

How to check application memory on Mac

The first thing to do if you’re getting an application memory issue notification is to track down the source of the problem. Being a detective and troubleshooter may not be easy, but there’s a tool to help you — Activity Monitor.

To see a list of all current processes on your Mac according to the resources they’re consuming, follow these steps:

  1. Go to Applications ➙ Utilities
  2. Launch Activity Monitor
  3. Click the Memory tab to see a list of processes, including apps and browser tabs that take up memory
  4. Select a process or app and click the X sign to close it

Memory tab

In the Memory tab, there will also be a graph showing an overview of your system's memory pressure. If the graph is green — you have enough disk space, if yellow or red — you’re short of memory. 

It’s a good habit to check Activity Monitor regularly, as it will allow you to take better control of the application memory Mac has and quit the apps running without your knowledge. Of course, regular checks and maintenance can take time, but fortunately, there are alternative ways to keep your Activity Monitor under control.

One of the most comprehensive Mac monitors to date is iStat Menus, which is a system data collector that lives in your menu bar and provides vital information about the key performance indicators. Stats about your memory load live behind one blue bar in iStat indicators. Once expanded, it shows the list of apps that take up most memory resources, general division of memory load, and the pressure that current usage has on your application memory Mac.

comprehensive Mac monitor

If your goal is to drastically reduce CPU usage, you will likely require the help of App Tamer. It spots idle apps that hog CPU in the background, and takes action slowing them down or stopping them to prevent application memory issues. App Tamer allows you to manually adjust which apps you want to control and how much CPU they can use while in the background.

App Tamer

While Activity Monitor is a good place to keep an eye on the processes going on in your Mac, some alternative apps will offer way more information and control, not to mention managing your macOS activity for you.

How to fix “your system has run out of application memory”

If your Mac is running painfully slow or those annoying error messages keep bothering you, it’s likely because your Mac is about to run out of application memory. To fix application memory issues and get your computer back up to speed, try one or a combination of the methods described below.

Force Quit unused applications

Apps running in the background use up a lot of virtual memory. If you are a multitasker, quitting unused applications should be the first method to try if your system has run out of application memory.

To Force Quit apps on your Mac:

  1. Press Option + ⌘+ Esc to open the Force Quit menu
  2. Click Force Quit to close programs you’re not currently using

Force Quit Applications

When you have used up all the application memory Mac, the Force Quit Applications window will open itself, suggesting you to quit some programs, but it’s a good practice to regularly close apps you’re not using.

For more efficiency in the Force Quit process, try using Quit All — an app designed to speed up your Mac by quitting all unnecessary apps in one click, rather than going through them one by one. It comes with a handy feature of viewing apps running in the background to be able to decide whether you want to close them or keep them at your discretion.

Quit All app

Limit the memory used by Finder

Finder is your Mac’s file manager, which searches all your files when you browse them, as well as stores the path of all your files in RAM. This process takes up a lot of RAM space, and limiting the memory used by Finder can be a great solution to all your application memory issues.

To avoid loading all your files when the Finder opens:

  1. Click Finder ➙ Preferences
  2. Click the drop-down list under General to select a folder, and don’t select “All my files” or “Recents” as the location
  3. Hold down the Control key and right-click the Finder icon
  4. Select Relaunch

With the help of iStat Menus, you can automate the process of controlling how much memory Finder, or any other program is using. The app collects data about your macOS performance and presents it in a clean format that’s easy to understand. Plus, it shows you a list of apps using the most memory at any given time, so you’re fully aware of the situation within your Mac.

Restore application

One or more apps open on your Mac right now may have a bug that causes them to hog memory. Check whether there are updates available for the apps using too much memory or use CleanMyMac X to reset application settings. 

This powerful app will clean, optimize, and protect your Mac for years of use. CleanMyMac X Uninstaller removes unnecessary apps completely, along with any files associated with them, while Updater allows you to keep useful apps up to date.

reset or uninstall apps with CleanMyMac X

Restart Mac regularly and keep macOS updated

Restarting your Mac clears the cache and other temporary files and gives back disk space used as virtual memory. It’s also a temporary but workable solution to mitigate the memory leak problem. Installing system updates regularly ensures your macOS is free of any bugs which might be the reason for some application memory Mac issues.

To check if there are any system updates available for your Mac now:

  1. Click on the Apple menu ➙ About This Mac
  2. Choose Software Update
  3. Follow the instructions on-screen to install the update if one is available

Software Update

Manage and clean up disk space

As mentioned, the best way to prevent application memory issues is to keep at least 10% of disk space free on your Mac.

To clean up disk space through Apple Storage Management, follow these steps:

  1. Click the Apple menu and select About This Mac
  2. Choose the Storage tab
  3. Press Manage
  4. Select Recommendations and you will see a list of things Apple recommends you do to free up storage space

Apple Storage Management

From here, decide which recommendations you want to take and follow the instructions. It’s a practical method, but very time-consuming, since you need to find the unwanted files and delete them one-by-one to free up space. But there is a simpler way. 

Run CleanMyMac X’s System Junk module regularly to keep as much disk space free as possible at all times. This tool identifies and removes all kinds of junk files, from temporary files that should have been deleted but weren’t to cache files and old logs. Freeing up several gigabytes of space with just a few clicks might have seemed impossible, but not anymore!

remove system junk using CleanMyMac X

Delete useless apps

Some applications use several gigabytes of space on your Mac, like Microsoft Word, which takes up to 2 GB, for example! So, if you’re not using an app, it makes sense to uninstall or delete it.

To delete unused apps through Finder:

  1. Locate the app in the Finder or use Spotlight to find it
  2. Drag the app to Trash, or select the app and choose File ➙ Move to Trash
  3. Choose Empty Trash to delete the app

Manage browser extensions

Excessive or buggy browser extensions may also be the reason for the “your system has run out of application memory” message to pop up on your Mac. Check your current extensions and decide whether they can be disabled or removed.

To manage extension in Safari, go to Preferences ➙ Extensions.

If you are using Chrome, access extensions by typing chrome://extensions in the address bar.

While extensions are helpful assistants when we are browsing, too many useless or outdated extensions could lead to application memory issues on your Mac.

Upgrade your Mac to a new Apple Silicon Mac

Apple is always upgrading its products based on consumer reports, and the latest software is likely to be free of the bugs and errors you encountered in the old version. If you are experiencing application memory issues on an Intel Mac, consider upgrading to the new Apple Silicon Mac using M1 chip, because that just might solve the issue!

What to do if Mac run out of application memory

As you now know, there are many reasons for the “system has run out of application memory” message to pop up, but all those reasons point to the same thing — a shortage of space on your hard drive. The simplest solution is to free up more space first using CleanMyMac X, force quit all the unused applications with Quit All, and then strengthen the results by keeping your system activity under control with the help from iStat Menus and App Tamer.

Good news! All four apps — CleanMyMac X, Quit All, iStat Menus, and App Tamer are available to you absolutely free through a seven-day trial of Setapp, a platform with more than 230 best-in-class macOS and iOS apps that can help unlock your Mac’s full potential. Try every Setapp app today at no cost and see how fast your Mac can really be.

Get 230+ Mac apps for any job

Sign up to Setapp and try them for free.