How to Fix "Your System Has Run Out of Application Memory" on Mac?

Have you encountered the error “your system has run out of application memory” on your Mac? Maybe you’ve seen the pop-up multiple times. But every time it’s confusing when you see the error message, especially when it appears out of nowhere.  

This problem is encountered a lot by Mac users. Sometimes, it can occur when you’ve got many apps open, when you upgrade to macOS, if you have a full RAM, and more. Whatever the reason may be, the fix is easier than you think.

A quick way to increase application memory on Mac is to force quit unused apps and use a third-party software, such as MacKeeper’s Smart Uninstaller. That way, you’ll be able to delete apps/files quickly and safely.

Now, we’ll dive into the causes of the pop-up error in more detail and show you how to fix it when your application memory is full on Mac.

What is application memory on a Mac?

Application memory on a Mac refers to the portion of RAM and virtual memory that macOS allocates for running apps and system processes. When too many apps or browser tabs are active, or when a single program consumes excessive resources, your system may display the “out of application memory” error.

Why has your system run out of application memory?

Now that we’ve gone over what application memory on a Mac is, let’s look at key reasons you might be seeing this pop-up error.  

Here are a few reasons why your system is out of application memory:

• The boot disc has little space for running applications
• Too many apps are running at the same time
• Immoderate browser extensions
• Applications that hog memory
• Excessive open browser tabs.

What does "your system has run out of application memory" mean?

We’ve noticed that macOS shows this alert when active apps, background processes, and the system consume most physical RAM, and there isn't enough free, fast swap space to keep going. In Activity Monitor > Memory, you'll see high App Memory, growing Compressed memory, and rising Swap Used. Close heavy apps and tabs, clear caches, uninstall unnecessary apps, or upgrade your hardware to reduce application memory on your Mac. Our experience shows that those steps collectively improve application memory on your Mac by lowering pressure and delays.

A note from our experts

 

The easy and quick way to get rid of “your system has run out of application memory” error on your Mac is to remove apps that you don’t need anymore and free up RAM. MacKeeper’s Smart Uninstaller removes the apps and their leftover files in a few moments.

 

Here’s how to remove apps/files safely with MacKeeper’s Smart Uninstaller:

1. Download MacKeeper and install the app.
2. Open MacKeeper and select Smart Uninstaller in the left side pane.
3. Click Start Scan.
4. Select what app, plugin, etc, you’d like to remove.
5. Click Remove Selected > Remove.

How to check application memory on Mac?

Before we take a look at the different steps to fix the error, go over how to check RAM usage. What for? That way, you can find out how much spare memory you have left.

Here’s how to check application memory on Mac:

1. Open Finder and click Applications.
2. Type in Activity Monitor in the search bar.

Now, you can see your memory usage, but you need to know what to look for.  

Here’s what this memory information means:

• App Memory - memory used by applications.
• Wired Memory - memory used by the system to function.
• Compressed - memory that’s compressed to make more RAM.
• Swap Used - the capacity to swap data to and from RAM.
• Cached Files - files cached by Mac to boost performance.

Observe the colored graph below the Memory Pressure. If there’s no red or yellow in your chart, then it shows that your Mac is running low on memory. Although it may seem contradictory, the amount of available storage on your Mac isn't indispensable.

By default, a system is designed to use as much memory as it can. However, you should still pay attention to the Memory Pressure graph in the Activity Monitor from time to time. Monitoring this parameter can be very useful and provide valuable insights into the performance of your system.

How to clear application memory on Mac

As we just went over, there are many reasons why you may be seeing this application memory error. Although, in some cases, the error can appear for no reason, the likelihood is the application memory is full on your Mac.  

Follow the steps below to fix app memory errors and get your Mac back running efficiently.

Restart your Mac

If your Mac keeps running out of application memory, restarting is the first step you should take. This clears the cache and some temporary files, thus giving back disk space.

Note: Before you restart your Mac, save any unsaved projects, documents, etc.

Here’s how to restart your Mac:

1. Click the Apple logo in the top left.
2. Select Restart.

Hopefully, simply restarting your Mac does the trick. If not, continue reading, and we’ll help you force quit unused apps.

Force quit unused apps

As running applications simultaneously can cause annoying memory pop-up errors, force quitting unused apps could be a quick way of fixing and preventing this issue. It's a simple process. Keep reading to find out how.

Follow these steps to force quit unused apps:

1. Hold these three keys down Option (or Alt), Command, Esc (Escape).
2. Alternatively, click the Apple logo and select Force Quit.
3. Select unused apps and click Force Quit.

Uninstall unnecessary apps

Unused apps still spawn helpers, daemons, and updaters that claim RAM and swap. We've found that removing heavy, rarely used tools can improve application memory on Mac more than closing a couple of tabs. The trade-off is time—clean removals take a few minutes.

Here’s how to do it:

1. Open Applications in Finder and sort by Size via View > as List, then View > Show View Options.
2. Drag unneeded apps to the Trash or, if they came from the App Store, long-press them in Launchpad and click the X.
3. Remove leftovers: in Finder, press Cmd+Shift+G, go to ~/Library/Application Support/ and ~/Library/Containers/, then delete folders named after the app.
4. Empty the Trash and restart the Mac.
5. Check Activity Monitor > Memory to confirm reduced App Memory.

Free up storage space

If the above steps didn’t work, you’ve likely run out of application memory. So, the next best step is to free up some disk space. There are a few ways to do so.

Here’s how to free up storage space:

1. If you have an external hard drive or storage device, transfer files/apps to it to free storage.
2. Next, delete files in the Downloads folder. Go to Finder, select Downloads, and delete any unwanted media/files.
3. Delete junk emails from the Mailbox. Open Mailbox > Erase Junk Mail in the menu. Then, in Mailbox > Erase Deleted Items.
4. Remove previous backups if you use your Mac to back up your devices.
5. Uninstall unused applications.
6. If you have user accounts set up on your Mac, delete them. Also, check the Users folder on Macintosh HD for any data of the deleted user accounts.
7. Look in the Users folder on Macintosh HD for any unwanted shared files.

Close browser tabs

Browsers can quietly consume memory, especially when dozens of media-heavy or poorly coded pages are open. We've seen memory pressure disappear the moment we tidy tabs. The upside is instant relief; the downside is you'll lose quick access to everything at once unless you bookmark key pages.

Here's how to reduce application memory on a Mac fast:

1. In Safari, choose Window > Close All Windows or press Cmd+Opt+W.
2. In Chrome, right-click a tab bar and pick Close other tabs.
3. In Firefox, right-click a tab and select Close Multiple Tabs > Close Other Tabs.
4. Bookmark must-keep sites first: Cmd+D in any browser.
5. Reopen just what you need and watch Activity Monitor > Memory to confirm lower pressure.

Manage browser extensions

As excessive extensions can cause application errors, we’ll go into how to manage your browser extensions in Chrome.  

Follow these steps to manage browser extensions:

1. Launch Chrome.
2. Click More (the three vertical dots in the top right) > Extensions > Manage Extensions.
3. Turn off excessive extensions.
4. If you have a corrupted extension, fix it by clicking Repair > Repair extension.

Extensions do come in handy, but many people use poor or outdated ones that can lead to storage errors popping up.

Clear cache and logs

Corrupted caches or ever-growing logs make macOS rely on swap sooner, which can trigger the warning. We clear them periodically—quick gains, minimal risk. But here’s the caveat: some apps will rebuild caches on the next launch, which is normal.

Follow these steps:

1. Quit all apps.
2. In Finder, press Cmd+Shift+G and open ~/Library/Caches/. Delete the contents of the folder, not the Caches folder itself.
3. Open /Library/Caches/ and clear safe app caches you recognize.
4. Open ~/Library/Logs/ and /Library/Logs/, then remove large, dated logs.
5. Restart the Mac to regenerate fresh caches.
6. Verify lower Memory Pressure in Activity Monitor.

Limit the memory usage by Finder

Finder is a common root cause for storage issues. You may have seen that Finder is taking up a lot of RAM when you checked in the Activity Monitor. If so, the fix is easy.

Here’s how to limit the memory usage by Finder:

1. Open Finder.
2. In the menu bar, select Settings.
3. Select the General tab. Under ‘New Finder windows show,’ make sure the option in the drop-down menu isn’t All My Files.
4. Close Preferences and relaunch Finder.

Stop apps starting up automatically

If you have too many apps opening every time you boot up your Mac, it could be the cause of RAM issues. Luckily, there’s a feature within System Preferences that acts as a startup manager. You can view all startup apps there, and disable some of them on the startup.

Follow these steps to stop apps from starting up automatically:

1. Select the Apple logo in the top left and click System Settings.
2. In the search bar, type in Login Items.
3. Pick a startup app to delete and select the minus button to remove it from the list.

Update your macOS

Sometimes, using an outdated macOS can cause application memory errors to pop up. Thus, updating your macOS is a safe bet. It’s easy to do with just a few steps.

Here’s how to update your macOS:

1. Click the Apple logo in the top left, and select System Preferences or System Settings.
2. If you have an update available, select Upgrade Now.
3. Regularly check for updates to prevent further application memory issues.

Add more RAM

When workloads grow, physical memory wins over any software tweak. We recommend upgrading on Macs with user-replaceable RAM; on most modern MacBooks, RAM is soldered, so use software tactics instead. For guidance and alternatives, see how to upgrade RAM on MacBook Pro and how to free up RAM on Mac.

For now, do the following:

1. Check upgradeability with Apple menu > About This Mac > More Info > System Report > Memory. Look for available slots or "Upgradeable."
2. If supported, buy matching RAM modules specified by Apple for your model.
3. Power down, unplug, and follow an Apple-approved guide to install the modules.
4. Boot and confirm capacity in About This Mac > Memory.
5. If your model isn't upgradeable, apply software fixes above and consider an SSD upgrade below to ease swap behavior.

Consider switching to SSD

An SSD doesn't increase RAM, but it makes swap operations far faster. We've seen older HDD-based Macs stop stuttering and reduce the frequency of alerts once they're moved to SSD. The downside is hardware cost and migration time.

Follow these instructions:

1. Check current drive: Apple menu > About This Mac > More Info > System Report > Storage.
2. For upgradeable Macs, replace the internal HDD with a SATA SSD; for others, use a fast USB-C or Thunderbolt NVMe enclosure.
3. Clone your disk with a reputable tool or restore from Time Machine to the SSD.
4. Set the SSD as the startup disk: System Settings > General > Startup Disk, then restart.
5. Monitor Activity Monitor > Memory—you should notice smoother performance when the system swaps.

Keep an eye on your application memory

After reading this article, you should now know how to fix the error “your system has run out of application memory” and prevent it from happening again.  

If you experience this issue again out of the blue, force quit the apps and restart your Mac. In addition, if you have a lot of browser tabs open, it's wise to close as many as possible, as this can be another cause of application memory problems. Usually, these temporary solutions will do the trick.  

We went over how to get more application memory on Mac. A great way is by staying up to date with your Mac using MacKeeper’s Smart Uninstaller. Removing leftovers, junk, and unused applications safely will help to prevent memory errors from reoccurring.