How to check your RAM before you clear it
Don’t start by closing things at random. Spend two minutes in Activity Monitor and find out whether memory is your problem at all.
- Open Activity Monitor from
/Applications/Utilities, or find it with Spotlight. - Click the Memory tab.
- Click the Memory column header to sort the biggest users to the top.
- Look at the Memory Pressure graph at the bottom of the window.
Read the memory pressure graph
Apple says a red memory pressure graph means your Mac needs more RAM. People commonly read green as healthy and yellow as strained, although those thresholds aren’t official. Apple also notes that unused memory doesn’t make a Mac faster, so a bar that looks full isn’t a problem on its own.
Know what each number means
| Number | What it is | What to do |
|---|---|---|
| App Memory | Memory your apps use right now | Quit the apps that use the most |
| Wired Memory | Memory macOS reserves for itself and can’t compress or move | Leave it alone |
| Compressed | Memory macOS squeezed to make room | Normal under load |
| Cached Files | Recently used files kept ready for speed | Normal, and macOS releases it on demand |
| Swap Used | Memory moved to your startup disk | Keep it low, and keep free disk space |
Swap Used
A high Swap Used number means macOS has moved memory to your startup disk. A little swap is normal. A lot of it, together with a red graph, means your apps want more memory than you have.
8 ways to free up RAM on a Mac
Work from the top. The first steps fix most slowdowns.
1. Quit the apps that use the most memory
In Activity Monitor’s Memory tab, select a heavy process and click the X button in the toolbar, then choose Quit. Use Force Quit only if the app doesn’t respond. Save your work first.
2. Close browser tabs and extensions
A browser is often the largest memory user. In Chrome, choose Window, then Task Manager, to see which tabs and extensions use the most. Close the heavy ones, or switch off extensions you don’t need.
3. Remove startup apps you don’t use
Open System Settings, then General, then Login Items & Extensions. Remove apps that launch at login without earning their keep.
4. Restart your Mac
A restart closes every process and clears accumulated memory. If your Mac has run for days or weeks, this single step often brings back the speed.
5. Update macOS and your apps
Updates fix memory leaks, so a slowdown that started recently may disappear after you update. Choose System Settings, then General, then Software Update.
6. Free up disk space
macOS swaps to your startup disk when RAM runs short, so a nearly full disk makes every memory problem worse. The section below explains how much space to keep free.
7. Check for one runaway process
If one process uses an unusual amount of memory for days, quit it, update the app that owns it and see whether it returns. If it does, contact that app’s developer.
8. Add memory only where you can
Some older Intel Macs have upgradable RAM, and System Information shows which kind you have. Apple silicon Macs use unified memory that you can’t upgrade, so the fix there is closing apps, or buying a model with more memory next time.
Match the symptom to the fix
| What you see | Likely cause | Fix |
|---|---|---|
| Beachball when switching apps | Red memory pressure | Quit heavy apps, then restart |
| Fans spin and the Mac feels slow | One app uses far too much | Quit or update that app |
| Slowdown only after days of uptime | A leaking app or process | Restart your Mac |
| Slow, and the disk is nearly full | Little room for swap files | Free up disk space |
| Slow with many browser tabs | Tabs hold memory | Close tabs and extensions |
Do memory cleaner apps work?
A Mac memory cleaner, or RAM cleaner, promises to free memory with one click. In practice, these apps empty cached files. The free-memory number jumps, then macOS refills the cache, and your apps reload data from disk, which is slower than reading it from memory.
Terminal tricks that claim the same result work the same way. Apple doesn’t document them as a fix, and the gain disappears within minutes. Spend your time on the real causes above instead.
A cleaner that does help
A disk cleaner helps indirectly. It doesn’t touch RAM, but it gives macOS free space for swap files and updates. Read our guide to freeing up space on a Mac for the safe places to start.
Why free disk space matters for memory
When memory runs short, macOS moves data to your startup disk and pulls it back when an app needs it. That only works well when the disk has room. Aim to keep 10 to 15 per cent of the disk free, and more if you edit video or run virtual machines.
Open System Settings, then General, then Storage to check your free space. If it is low, our guide on how to free up space on a Mac lists 14 safe ways to make room, and MyMacStorage does the same job in one scan.
MyMacStorage is a native Mac storage cleaner that costs £14.99 once. It scans on your Mac, lists every file before it clears anything and moves it to the Bin. Learn more on the home page.