Quickfix AI
Easy•15 min

How to speed up a slow Mac

If your Mac has started lagging, freezing, or taking forever to open apps, the cause is often something simple like too many background apps, low storage, or a pending update. This guide walks you through the quickest, safest ways to speed up a slow Mac on macOS. Start at the top and stop when your Mac feels normal again.

Symptoms

  • Apps open slowly
  • The Mac feels laggy when switching between windows
  • The beachball appears often
  • The fan runs loudly more than usual
  • Files, downloads, or webpages take longer than normal to load

Step-by-step fix

  1. 1

    Restart your Mac

    A restart clears temporary system clutter and closes apps or processes that may be slowing everything down. Click Apple menu , then choose Restart. After the Mac turns back on, use it for a few minutes to see whether it feels faster.

  2. 2

    Close apps you are not using

    Too many open apps can use memory and processor power. To close one, click the app name in the top-left menu bar, then choose Quit. You can also press Command ⌘ + Q inside the app. If an app is frozen, press Option ⌥ + Command ⌘ + Esc, select the app, then choose Force Quit.

  3. 3

    Check Activity Monitor for heavy processes

    Activity Monitor shows what is using your Mac’s CPU, memory, disk, or energy. Open Applications > Utilities > Activity Monitor. In the CPU tab, look for apps using a lot of percentage, especially if you are not actively using them. If something obvious is consuming a lot of resources, quit that app and see whether performance improves.

  4. 4

    Free up storage space

    macOS needs free space to work smoothly, especially for updates and temporary files. Click Apple menu > System Settings > General > Storage to see what is taking up space. Remove large files you no longer need, empty the Trash, and consider moving photos, videos, or downloads to external storage or cloud storage. As a general rule, keep at least 10 to 15 GB free if possible.

  5. 5

    Install macOS updates

    Updates can improve performance, fix bugs, and patch problems that make a Mac sluggish. Go to Apple menu > System Settings > General > Software Update. If an update is available, follow the prompts to install it. Keep your Mac plugged into power during the update.

  6. 6

    Reduce startup items

    Some apps open automatically when you sign in, which can slow down startup and make the Mac feel busy right away. Open System Settings > General > Login Items. Under Open at Login, select apps you do not need at startup and remove them using the minus button or Delete key if available. Also review the Allow in the Background section and turn off anything you do not recognize or need.

  7. 7

    Check for low battery and overheating

    Macs can slow down to manage heat or save power. If you are on a MacBook, connect it to power and see whether performance improves. Make sure vents are not blocked, and avoid using the Mac on a soft surface like a bed or couch. If the Mac is very hot, let it cool down for a few minutes and close demanding apps such as video editors, games, or multiple browser tabs.

  8. 8

    Run Disk Utility First Aid

    If the Mac is still slow, the built-in disk check can help find and repair certain storage-related issues. Open Applications > Utilities > Disk Utility. Select your startup disk, usually named Macintosh HD, then click First Aid and follow the prompts. Your Mac may pause briefly while it checks the disk.

Frequently asked questions

Why is my Mac suddenly so slow?

The most common reasons are too many apps running, not enough free storage, a macOS update waiting to be installed, or a process using too much CPU or memory. Restarting the Mac and checking Activity Monitor usually helps identify the cause.

Does low storage make a Mac slower?

Yes. When storage is nearly full, macOS has less room for temporary files, cache, and virtual memory, which can make the system feel sluggish. Freeing up space often improves responsiveness quickly.

How much free space should I keep on my Mac?

Try to keep at least 10 to 15 GB free for smooth day-to-day use. If you edit large photos or videos, keeping even more space free can help.

Will restarting my Mac delete anything?

No. Restarting closes open apps and refreshes macOS, but it does not delete your files. If you have unsaved work, save it before restarting.

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