How to Clear Application Memory on Mac in 2025 (Fix the RAM Warning)

If your Mac has displayed the message "Your system has run out of application memory," you know how alarming it feels — apps freeze, the cursor becomes a spinning beachball, and the system grinds to a halt. Knowing how to clear application memory on Mac is a genuinely useful skill that gets you out of that situation fast and helps prevent it from happening again. This guide explains what application memory actually is, what causes the error, and gives you concrete, step-by-step actions to fix it right now.

Table of Contents

• What Is Application Memory on Mac?
• Why Does Mac Run Out of Application Memory?
• Quick Fix Summary
• 1. Force Quit Memory-Hungry Apps
• 2. Use Activity Monitor to Find the Culprit
• 3. Purge RAM via Terminal
• 4. Reduce Browser Tab Count
• 5. Disable Login Items and Background Agents
• 6. Clear Virtual Memory Swap Files
• 7. Long-Term Fixes: Upgrade RAM or Optimize Workload
• FAQ
• Conclusion

What Is Application Memory on Mac?

Application memory on Mac is the portion of your physical RAM (Random Access Memory) that is allocated to running apps and processes. When you open an app — Safari, Photoshop, Slack, Zoom — macOS loads it into RAM so the processor can access it quickly. The more apps you have open, and the heavier each app is, the more application memory gets used.

macOS uses a memory management approach called unified memory on Apple Silicon Macs (M1, M2, M3, M4) and a similar system on Intel Macs. The OS tries to be smart about memory: it compresses data for inactive apps ("Memory Used" vs. "Memory Compressed" in Activity Monitor) and spills overflow to the SSD via swap files. But when real demand outpaces what compression and swap can handle, you get the "Your system has run out of application memory" alert.

This is different from storage space on your hard drive. Application memory is the live RAM your CPU and GPU are actively using right now. Running out of it means there is literally no place to put the data that running applications need.

Why Does Mac Run Out of Application Memory?

Several factors push RAM to its limits, and most Macs hit this point under the right combination of conditions.

• Too many apps open simultaneously — every open app consumes RAM even when minimized or in the background
• Browser tabs — each open tab in Chrome, Firefox, or even Safari can use 100–500 MB of RAM; 20 tabs can easily consume 3–8 GB
• Memory leaks in apps — some apps gradually consume more and more RAM over time without releasing it, even when idle; restarting the app is the only fix
• Heavy creative applications — Photoshop, Final Cut Pro, Logic Pro, DaVinci Resolve, and Xcode are all designed to use large amounts of RAM for performance
• Video conferencing software — Zoom, Teams, and Google Meet consume significant RAM during calls, especially with video on
• Low physical RAM — Macs with 8 GB of RAM are particularly susceptible as modern macOS and apps have grown in their baseline memory footprints
• Background processes — cloud sync clients (Dropbox, Google Drive, OneDrive), antivirus software, and menu bar utilities all consume RAM
• Virtual machines — Parallels and VMware Fusion allocate a fixed block of RAM for their virtual machine, often 4–8 GB
• macOS itself — the OS reserves a portion of RAM, so on an 8 GB Mac you may only have 5–6 GB available to apps before the system and kernel processes take their share

Quick Fix Summary

1. Force Quit Memory-Hungry Apps

The Fastest Way to Reclaim RAM Right Now

When the out-of-application-memory alert appears, your first move should be quitting apps you are not actively using. Force quitting is appropriate when an app is unresponsive.

Method 1 — Force Quit menu:

1. Press Command + Option + Escape to open the Force Quit Applications window
2. You will see all open apps listed, with unresponsive ones showing "(Not Responding)" in red
3. Select the app you want to quit
4. Click Force Quit
5. Confirm in the dialog that appears

Method 2 — From the Dock:

1. Hold Option and right-click any app icon in the Dock
2. The normal "Quit" option changes to Force Quit
3. Click it

Method 3 — From the Apple menu:

1. Click the Apple logo () in the top-left corner
2. Select Force Quit
3. Choose the target app and click Force Quit

Tip: Even if an app is technically "responding," quitting it while you are not using it still frees up its RAM allocation. You do not need to wait for an app to freeze — proactively quitting unused apps is good practice when memory is low.

2. Use Activity Monitor to Find the Culprit

Identify the Exact Process Consuming the Most Memory

Activity Monitor is macOS's built-in task manager. It shows every running process with its exact memory usage — essential for knowing what to target.

Steps:

1. Open Activity Monitor from Applications > Utilities, or press Command + Space, type Activity Monitor, and hit Return
2. Click the Memory tab at the top of the window
3. Click the Memory column header to sort by memory usage — highest at the top
4. Look at the Memory Used figure at the bottom of the window. Also note Swap Used — if swap is high, your system is already writing RAM to disk
5. Identify the top 3–5 processes consuming the most memory

Reading the Memory Pressure graph:

• Green — memory is healthy, no pressure
• Yellow — memory is under moderate pressure, the system is managing
• Red — memory pressure is critical; the system is actively struggling

To quit a process from Activity Monitor:

1. Select the process row
2. Click the X (Stop) button in the top-left toolbar of Activity Monitor
3. Choose Force Quit for unresponsive processes or Quit for normal ones

Tip: The process named kernel_task will sometimes appear near the top. Do not quit this — it is the macOS kernel. Similarly, avoid quitting processes like WindowServer, loginwindow, or launchd. Focus on named applications you recognize.

You can also check memory from Terminal for a quick snapshot:

vm_stat

Look at the "Pages free," "Pages active," "Pages inactive," and "Pages wired down" lines. Multiply page counts by 4096 (4 KB per page) to convert to bytes.

3. Purge RAM via Terminal

Force macOS to Reclaim Inactive Memory

macOS sometimes holds onto "inactive" memory — data from apps you have already quit that the OS keeps cached in case you reopen them. This is normal behavior, and macOS is supposed to reclaim it automatically when needed. Sometimes, though, it is useful to manually force that reclamation.

Steps:

1. Open Terminal from Applications > Utilities
2. Type the following command and press Return:

sudo purge

3. Enter your administrator password when prompted (the cursor will not move as you type — that is normal)
4. Press Return
5. Wait 10–20 seconds while macOS clears inactive memory

After the command completes, open Activity Monitor and check the Memory tab. The "Memory Used" figure should drop, and the "Memory Pressure" graph should improve if inactive memory was the culprit.

Tip: The purge command only clears inactive memory — it will not free up memory that apps are actively using. If your system is still under pressure after purging, that means active applications are using all available RAM, and you need to quit some apps.

4. Reduce Browser Tab Count

The Single Biggest Source of RAM Consumption for Most Users

Browser tabs are the most underappreciated source of memory pressure on Mac. Each Chrome or Firefox tab runs in its own process and can consume anywhere from 50 MB to 500 MB depending on the page. A person with 30 tabs open in Chrome might be using 4–10 GB of RAM in the browser alone.

Steps to identify and close heavy tabs in Chrome:

1. In Chrome, press Shift + Escape to open Chrome's Task Manager
2. Click the Memory footprint column to sort tabs by RAM usage
3. Close tabs consuming the most memory that you do not actively need
4. Consider bookmarking tabs you want to return to rather than leaving them open

Steps to reduce tab memory in Safari: Safari is more memory-efficient than Chrome, but tabs still add up.

1. In Safari, go to Window in the menu bar and review all your open tabs
2. Right-click the tab bar and select Close Other Tabs if there are many you are not using
3. Enable Safari > Settings > Advanced > Reload Page on Visit — this option loads pages only when you switch to them rather than keeping them live in memory

Alternative: Use a tab suspension extension

For Chrome users, extensions that suspend inactive tabs (by replacing them with placeholder pages) can dramatically cut memory usage. The tab reloads when you click it. Search the Chrome Web Store for "tab suspender" to find current options.

Tip: A practical habit is to use bookmarks or a reading list app for content you want to read later, rather than leaving tabs open indefinitely. This alone can keep Chrome's memory footprint under 1 GB instead of 5–8 GB.

5. Disable Login Items and Background Agents

Cut Background RAM Usage at the Source

Login items are applications that launch automatically when you log in to your Mac. Background agents are helper processes run by apps even when the main app is closed. Both consume RAM around the clock.

Steps to review and disable login items:

1. Open Apple menu > System Settings
2. Click General in the left sidebar
3. Click Login Items & Extensions
4. Under the Open at Login section, you will see a list of apps that start automatically
5. Select any app you do not need at startup
6. Click the minus (–) button to remove it from the list

Tip: Common login items that are safe to disable for most users include: cloud storage clients (Dropbox, OneDrive, Google Drive) if you do not need constant sync, communication apps (Slack, Teams, Zoom), and utility apps (Alfred, Bartender, CleanMyMac). You can still open these apps manually when you need them — removing them from login items just prevents them from consuming RAM when you are not using them.

Check for background agents in Activity Monitor:

1. Open Activity Monitor (Applications > Utilities)
2. Click the Memory tab
3. Look for processes with names like DropboxMacUpdate, GoogleDriveFSHelper, OneDriveStandaloneUpdater, or similar
4. These are background helpers running without a visible app window
5. To permanently stop them, disable the parent app from login items as described above, or configure the parent app's settings to not run in the background

6. Clear Virtual Memory Swap Files

How Swap Affects Application Memory Performance

When application memory runs out, macOS starts writing RAM contents to the SSD — this is called swap. Swap files make it possible to keep running when RAM is exhausted, but they make everything significantly slower because SSD access is much slower than RAM. If your Mac is crawling and the "Memory Pressure" graph in Activity Monitor shows red, swap is likely involved.

The safest and most complete way to clear swap files is to restart your Mac.

Steps:

1. Save all open work in every app
2. Click Apple menu > Restart
3. Your Mac will restart, clearing all swap files in the process
4. When macOS boots fresh, it starts with clean memory allocation

To check swap usage before restarting:

sysctl vm.swapusage

Look for the used value. If it is several gigabytes, a restart will give you noticeable improvement.

Tip: If restarting is not an option right now, closing the most memory-hungry apps (identified in Activity Monitor) will cause macOS to pull data back from swap into RAM, reducing the swap footprint gradually. But nothing clears swap completely except a restart.

7. Long-Term Fixes: Upgrade RAM or Optimize Workload

When the Problem Is Structural

If you regularly hit the out-of-application-memory warning and the above fixes only provide temporary relief, the underlying issue is that your workload exceeds your Mac's RAM capacity. There are two paths forward.

Option A: Upgrade RAM (Intel Macs)

On Intel-based Macs, RAM is sometimes user-upgradeable. Check your specific model:

1. Click Apple menu > About This Mac
2. Check your Mac model and year
3. Search "[your model] RAM upgrade" to see if the RAM is soldered or accessible

Tip: MacBook Pros from 2015 and earlier, iMacs, and Mac Pros often allow RAM upgrades. MacBooks from 2016 onward and all Apple Silicon Macs (M1, M2, M3, M4) have soldered RAM that cannot be upgraded. If you have an Intel Mac with upgradeable RAM, doubling from 8 GB to 16 GB is one of the best performance investments you can make.

Option B: Optimize Your Workload (All Macs)

If your RAM cannot be upgraded (including all Apple Silicon Macs), managing what you run simultaneously is the only way to prevent memory exhaustion.

Strategies that genuinely help:

• Reduce the number of browser tabs you keep open at any given time — aim for fewer than 10
• Quit apps completely when not in use rather than leaving them in the Dock
• Use Safari instead of Chrome — Safari uses significantly less RAM for equivalent browsing
• Close virtual machines when not actively using them
• In Xcode or creative apps, close projects and files you are not currently working on
• Configure cloud sync clients to run on a schedule rather than continuously

Check your current memory baseline after a fresh restart:

1. Restart your Mac and do not open any apps
2. Open Activity Monitor > Memory tab
3. Note how much "Memory Used" is shown just from macOS itself
4. This tells you how much RAM the OS and background processes consume before you open a single app, helping you plan how many apps you can realistically run

FAQ

What does "Your system has run out of application memory" mean on Mac?

This error means your Mac has exhausted its available RAM and cannot allocate enough memory to keep all running apps functioning. macOS manages RAM through compression and swap files, but when demand exceeds what those mechanisms can handle, the system displays this alert. The immediate fix is to quit one or more open applications to free up RAM.

What is application memory on Mac vs. storage space?

Application memory (RAM) and storage (disk space) are entirely separate resources. RAM is fast, temporary memory that apps use while running — its contents disappear when you shut down. Storage is your SSD or hard drive, where files are permanently saved. Running out of application memory means RAM is full; running out of storage means your SSD is full. The fixes for each problem are completely different.

Why does my Mac keep running out of application memory even after restarting?

If your Mac runs out of memory quickly after a fresh restart, your workload likely exceeds your Mac's RAM capacity. Check Activity Monitor's Memory tab right after restarting (before opening any apps) to see the OS baseline, then watch how memory climbs as you open apps. The most RAM-intensive culprits are usually Chrome with many tabs, video editing apps, Zoom calls, and virtual machines running simultaneously. Reducing what you run at once is the sustainable solution.

Can I clear application memory on Mac without restarting?

Yes. Use sudo purge in Terminal to force macOS to reclaim inactive memory, force quit unused applications through Command + Option + Escape, and close browser tabs. These steps free up memory without requiring a restart. However, a restart is the most thorough method and clears swap files too.

Does more RAM actually make a Mac faster?

For users who regularly hit the out-of-application-memory error or see a red Memory Pressure graph in Activity Monitor, more RAM makes a significant difference. When the system is not using swap, app launches are faster, multitasking is smoother, and the spinning beachball disappears. For users who rarely push their Mac hard, the benefit is less dramatic. If you have 8 GB and regularly run Chrome, Slack, Zoom, and a creative app at the same time, upgrading to 16 GB (on eligible Intel Macs) will be one of the most noticeable performance upgrades you can make.

Conclusion

The "Your system has run out of application memory" warning is your Mac telling you it needs relief — and the fixes are straightforward once you know where to look. Start by force quitting unused apps and using Activity Monitor to find the specific process eating the most RAM. Close excess browser tabs, disable unnecessary login items, and use sudo purge in Terminal for an immediate cleanup. If the problem recurs despite those steps, optimizing your workflow — fewer simultaneous apps, Safari over Chrome, closing virtual machines — is the sustainable path on Macs whose RAM cannot be upgraded. Taking these steps not only resolves the immediate error but keeps your Mac running smoothly under normal daily load.