What's using your Mac's memory and how to see it
When your Mac slows down, the problem is often that applications are using too much of your available memory — also called RAM. You can see exactly which programs are consuming memory by opening Activity Monitor, a built-in tool that shows you real-time information about what your Mac is doing.
To open Activity Monitor, press Command + Space to open Spotlight search, type "Activity Monitor", and press Enter. Once it opens, click the "Memory" tab at the top. You'll see a list of every application currently running, ranked by how much memory each one is using. The column labeled "Memory" shows the amount in megabytes (MB) or gigabytes (GB). At the bottom of the window, you'll see "Memory Pressure" — a colored indicator that tells you whether your Mac has enough free memory or is running low.
Green memory pressure means your Mac has plenty of free memory and is running smoothly. Yellow or red means applications are competing for limited memory, which causes slowdowns. This is the signal that you need to free up space.
Key Takeaways
- Activity Monitor shows you which applications are using the most memory; open it through Spotlight search and click the Memory tab.
- Closing applications you're not actively using is the fastest way to free up memory, especially web browsers with many tabs open.
- Restarting your Mac clears memory used by background processes and is often more effective than closing individual applications.
- Safari and Chrome can use significant memory when you have many tabs open; closing unused tabs or windows reduces memory pressure immediately.
- If memory pressure stays red even after closing applications, your Mac may not have enough physical RAM for your typical workload.
Close applications you're not using right now
The simplest way to free up memory is to quit applications you've opened but aren't actively using. Many people keep applications running in the background without realizing they're consuming memory. Web browsers are the most common culprit — each open tab uses memory, and a browser with 20 or 30 tabs can use several gigabytes.
To close an application, click its name in the menu bar at the top of your screen and select "Quit [Application Name]", or press Command + Q while the application is active. You can also right-click an application icon in the Dock and select "Quit". If you see an application in Activity Monitor using an unusually large amount of memory, you can select it and click the "X" button labeled "Force Quit" — though this should be a last resort, as it closes the application without saving open work.
Start by closing applications you opened hours ago and forgot about. Check your Dock for programs you don't need right now. Close extra browser tabs and windows, especially if you have multiple browser windows open at once.
Restart your Mac to clear memory completely
Restarting your Mac clears all memory used by applications and background processes, giving you a fresh start. This is often more effective than closing individual applications because it also clears temporary files and processes that accumulate over time. Many Mac users find that a restart solves memory problems that closing applications alone did not fix.
To restart, click the Apple menu in the top-left corner, select "Restart", and click "Restart" again to confirm. Your Mac will close all open applications (you'll be prompted to save any unsaved work), shut down, and start up again. The entire process usually takes two to five minutes depending on how many applications you have set to open at startup.
If you don't want to lose your open windows and documents, macOS can restore them when you restart. Before restarting, you can also check "Reopen windows when logging back in" in the restart dialog, which will restore your applications and windows to the state they were in before the restart.
Reduce the number of browser tabs and extensions
Web browsers — Safari, Chrome, Firefox, and Edge — are among the heaviest memory users on most Macs. Each open tab runs its own processes and loads content into memory. If you have 30 tabs open across two browser windows, your browser alone might be using 2 to 4 gigabytes of RAM.
Start by closing browser tabs you're not actively reading. If you want to keep a tab for later, bookmark it instead of leaving it open. Close entire browser windows if you have multiple windows open. If you use Chrome, it typically uses more memory than Safari because Chrome runs each tab in a separate process for stability — this makes Chrome safer but heavier on memory.
Browser extensions also consume memory, especially if you have many installed. To see which extensions are using the most memory in Chrome, open Activity Monitor and look for processes labeled "Chrome Helper" — each one represents a tab or extension. In Safari, you can disable extensions by going to Safari menu > Settings > Extensions, then unchecking extensions you don't use regularly.
Check for applications running in the background
Some applications continue running in the background even when you're not actively using them. Mail, Slack, Discord, and other communication apps often stay open to receive notifications. Cloud storage applications like Dropbox and Google Drive sync files in the background. These are useful for their intended purpose, but if you're trying to free up memory, you can quit them temporarily.
Open Activity Monitor and look through the list for applications you recognize but didn't intentionally open. Common background processes include Slack, Mail, Dropbox, and various system services. If you see an application using significant memory that you don't need right now, select it and close it. You can always reopen it later.
Be cautious about closing system processes — anything with "kernel", "system", or "daemon" in its name should generally be left alone, as these are essential to your Mac's operation. Stick to closing user-facing applications like messaging apps, email clients, and cloud storage tools.
Disable login items if applications start automatically
Your Mac can be set to automatically open certain applications every time you restart. These are called login items. If you have many applications set to open at startup, they all load into memory at once, which can slow down your Mac significantly. You can see and remove login items through System Settings.
Click the Apple menu, select "System Settings", then go to "General" and click "Login Items". You'll see two sections: "Allow in the Login Window" and "Open at Login". The "Open at Login" section shows applications that start automatically when you restart. Remove any applications you don't need to open every time you start your Mac by clicking the minus button next to them.
This won't free up memory immediately, but it will reduce memory pressure the next time you restart your Mac. If you have 10 applications set to open at login, removing half of them can noticeably improve your Mac's performance after restart.
When memory problems mean you need more RAM
If your memory pressure stays red or yellow even after closing applications and restarting, your Mac may simply not have enough physical RAM for the work you're doing. This is especially common if you use memory-intensive applications like video editing software, music production tools, or virtual machines.
You can check how much total RAM your Mac has by clicking the Apple menu, selecting "About This Mac", and looking at the "Memory" line. Most modern Macs come with 8, 16, or 24 gigabytes of RAM. If you consistently see red memory pressure and you're doing demanding work, upgrading your RAM may be the only lasting solution. On newer Macs with Apple silicon chips (M1, M2, M3, and later), RAM is built into the processor and cannot be upgraded after purchase. On older Intel-based Macs, RAM can sometimes be upgraded by a technician.
Before considering an upgrade, try the steps above for at least a week. Many memory problems are solved by closing unnecessary applications and restarting regularly. Only if the problem persists despite these changes should you consider that your Mac needs more RAM.
Frequently Asked Questions
Is it bad to force quit an application?
Force quitting closes an application without saving your work, so you'll lose any unsaved documents or data in that program. Use it only when an application is frozen and won't respond to normal quit commands. For applications that are simply using too much memory, closing them normally through the menu or Command + Q is better because it gives you a chance to save your work first.
Why does my Mac still slow down after I close applications?
Closing applications frees up memory, but slowness can also come from your hard drive or processor being overloaded. Open Activity Monitor and check the "CPU" tab to see if any application is using a very high percentage of processor power. If your Mac is still slow after memory pressure returns to green, the problem may be something other than memory.
Will restarting my Mac delete my files?
No. Restarting shuts down your Mac and starts it up again, but it doesn't delete any files. All your documents, photos, and applications remain on your Mac after restart. You may lose unsaved work in open applications if you don't save before restarting, but your Mac's storage is not affected.
Should I leave my Mac on all the time to avoid restarting?
No. Restarting regularly — once a week or every few days — actually improves performance by clearing memory and temporary files. Leaving your Mac on continuously can cause memory pressure to build up over time. A weekly restart is a good habit for keeping your Mac running smoothly.
What's the difference between memory and storage on a Mac?
Memory (RAM) is temporary space your Mac uses to run applications right now. Storage is permanent space where your files and applications are saved. Freeing up memory makes your Mac faster while you're using it. Freeing up storage (by deleting files) makes room for new files but doesn't improve performance unless your storage drive is completely full.