Mac running slow? 8 fixes to try

howtosimply.com/guides/mac-running-slow-8-fixes-to-try/ · Checked 4 October 2026 · MacBook Pro · macOS Tahoe 26

4 of 8 steps with real screenshots · 5 official sources below

Device

Mac

Shown on

macOS Tahoe 26 (MacBook Pro)

App

System Settings

Real screenshots

4 of 8 steps

Checked

4 October 2026

Sources

5 official, linked below

Find the likely cause

• If the Mac has not been restarted for days or weeks, restart it first (step 1).
• If one app stays at the top of the CPU list, quit it (step 2) and see whether the Mac speeds up before trying anything else.
• If the Mac slows down when many apps or browser tabs are open, check Memory Pressure (step 3) and close what you do not need.
• If the storage bar is nearly full, see what is filling the disk and use the recommendations (steps 4 and 5).
• If the Mac is slow from the moment you log in, trim the apps that open at login (step 6).

Step by step

1. 

   Restart

   Click the Apple menu and choose Restart. If you normally only close the lid, the Mac may have been running for weeks.

   Done

2. 

   Find the app that is using everything

   Open Activity Monitor from Applications, Utilities, or press Command + Space and type its name. On the CPU tab, click the % CPU column to sort. An app that stays near the top at a high percentage is the cause. Select it and click the X button to quit it.

   Done

3. 

   Look at Memory Pressure

   On the Memory tab, the graph at the bottom should be green. Yellow or red means too many apps and browser tabs are open. Close some.

   Done

4. Free up storage

   A nearly full disk slows macOS badly. Our guide: how to check and free up storage on a Mac.

   Done

5. Trim login items

   Fewer apps starting by themselves means more memory for your work: how to stop apps opening at login.

   Done

6. Close browser tabs and remove extensions

   Each tab is a small app. Dozens of tabs and several extensions can use more memory than everything else together.

   Done

7. 

   Update macOS and your apps

   Open System Settings, General, Software Update. Update apps in the App Store under Updates.

   Done

8. Give it time after an update

   After a big macOS update, the Mac re-indexes files for search and Photos for a few hours. It is slow and warm during that time and recovers by itself when left on and plugged in.

   Done

About this guide

A slow Mac is usually short of memory or storage, or has one app misbehaving in the background. The Mac has a built-in tool that shows which.

Good to know

If the fans are loud and the Mac is hot, check that the vents are not blocked and that it is not sitting on a blanket.

You do not need a "cleaner" app. Many are aggressive adverts, and some are malware.

An older Mac with a mechanical hard disk and 8 GB of memory or less will stay slow with current software whatever you do.

In short: Apple menu > Restart… > Activity Monitor > System Settings > General > Storage > Login Items & Extensions > Software Update > App Store > Updates

📷 Camera Lab: the same 6 scenes photographed with 11 phones, side by side.