A Mac that once felt snappy can start to drag over time — apps take longer to open, the spinning wheel appears more often, and the fans kick in during simple tasks. The good news is that most slowdowns have a clear, fixable cause: an app using too much memory or processor time, too many items launching at startup, a nearly full startup disk, or software that needs updating. This guide walks you through how to find out what is actually slowing your Mac down and how to fix it using only the tools Apple builds into macOS.
What You’ll Need
- Your Mac and its administrator password (some settings require it).
- About 20–30 minutes for a full check.
- A recent backup, ideally with Time Machine or another backup tool, before you delete files or install major updates.
- An internet connection if you plan to check for software updates.
Step 1: Restart Your Mac
It sounds basic, but a restart clears out memory, ends stuck background processes and finishes pending updates. If you usually close the lid instead of shutting down, your Mac may have been running for weeks. Choose the Apple menu > Restart. When prompted, you can uncheck the option to reopen windows when logging back in so you start with a clean slate.
Step 2: Use Activity Monitor to Find the Culprit
Activity Monitor is the single most useful tool for diagnosing a slow Mac. Open it from Applications > Utilities > Activity Monitor, or press Command + Space and type “Activity Monitor.”
- Click the CPU tab, then click the % CPU column header to sort by usage. Any app consistently near the top using a large share of the processor while you’re not actively using it is a likely cause.
- Click the Memory tab and look at the Memory Pressure graph at the bottom. Green means memory is fine; yellow or red means your Mac is running short and is relying heavily on slower swap space.
- If an app is misbehaving, save your work in it first, then select it and click the Stop (X) button in the toolbar to quit it. Use Force Quit only if a normal quit doesn’t work.
Web browsers with dozens of open tabs are among the most common memory hogs. Closing unused tabs or windows often makes an immediate difference.
Step 3: Reduce Login Items and Background Apps
Many apps quietly add themselves to your startup routine. Each one uses memory and processing power from the moment you log in.
- Open System Settings (called System Preferences on older versions of macOS).
- Go to General > Login Items (the label may read “Login Items & Extensions” on newer releases).
- Under Open at Login, select apps you don’t need right away and click the minus (–) button.
- Review the Allow in the Background list and switch off items you don’t recognize or no longer use. Don’t disable security software or backup tools you rely on.
Restart afterward to see the effect.
Step 4: Free Up Storage Space
macOS needs free space on the startup disk for virtual memory, caches and updates. When the disk is nearly full, performance can drop sharply. As a general rule of thumb, try to keep a healthy chunk of space free — at least 10–15% of the drive.
- Go to System Settings > General > Storage (or Apple menu > About This Mac > Storage on older versions).
- Review the built-in Recommendations, such as storing files in iCloud, optimizing storage for TV and movie downloads, and emptying the Trash automatically.
- Click the info button next to categories like Applications or Documents to find large or unused files you can remove.
- Empty the Trash when you’re done — deleted files still take up space until you do.
Step 5: Update macOS and Your Apps
Apple regularly releases updates that fix bugs and performance issues. Go to System Settings > General > Software Update to check for macOS updates, and open the App Store and click Updates for apps installed from there. Apps downloaded from the web usually have their own “Check for Updates” option in their app menu. An outdated app that isn’t optimized for your version of macOS can be a hidden source of slowdowns.
Step 6: Try Safe Mode
Safe mode starts your Mac with only essential software and performs some basic disk checks. If your Mac runs noticeably faster in safe mode, a login item, extension or third-party app is likely the cause.
- Mac with Apple silicon: Shut down. Press and hold the power button until “Loading startup options” appears. Select your startup disk, then press and hold Shift and click Continue in Safe Mode.
- Intel-based Mac: Restart and immediately press and hold Shift until the login window appears.
Restart normally to leave safe mode.
Common Problems and Fixes
- Mac is slow right after a major macOS update: For a while after an update, macOS may reindex Spotlight and optimize system files in the background. Leave the Mac on and plugged in for a few hours; performance often returns to normal on its own.
- Fans are loud and the Mac feels hot: Check the CPU tab in Activity Monitor for a runaway process. Make sure the vents aren’t blocked and avoid using a laptop on soft surfaces like beds or cushions.
- Only one app is slow: Update that app, restart it, and check the developer’s support site. If it continues, deleting and reinstalling it can help.
- Memory Pressure stays yellow or red: Run fewer apps at once, close browser tabs and quit apps you aren’t using. If it happens with your normal workload, your Mac may simply need more memory than it has for the way you use it.
- Startup takes a very long time: Trim login items as described above and check that the startup disk has plenty of free space.
Protect Your Data While Troubleshooting
Before deleting large files, removing apps or installing a major macOS upgrade, back up your Mac. Time Machine, built into macOS, can back up to an external drive. Be cautious with third-party “cleaner” or “optimizer” apps that promise dramatic speed boosts — some are unnecessary, and some ask for deep system access or push paid upgrades. Download software only from the App Store or developers you trust, and never disable built-in security features to speed things up.
Frequently Asked Questions
Do I need a cleaning app to speed up my Mac?
Usually not. Activity Monitor, Login Items settings, the Storage panel and Software Update cover the most common causes of slowdowns without installing extra software.
How often should I restart my Mac?
There is no fixed rule, but restarting every week or so, and whenever you notice sluggishness, helps clear memory and apply pending updates.
Will resetting my Mac to factory settings make it faster?
It can help if the problem is caused by software, but it erases your data. Treat it as a last resort and make a full backup first.
When should I contact Apple Support?
If your Mac is still slow after these steps, runs slowly even in safe mode, or shows other signs of hardware trouble, contact Apple Support or visit an Apple Authorized Service Provider. You can also run Apple Diagnostics to check for hardware issues.
Steps and menu labels may change as apps update. Last updated: November 2026.