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Despite the fact that the Mac operating system is quite stable and responsive, over time you may find your Mac running slow. There may be various reasons for a decline in Mac’s performance. In this article, we will help you to analyze why your Mac is running slow and explain how to improve Mac performance.
Why is my Mac running slow
The first step to diagnosing a system slowdown is to consider the most common reasons that may cause this. If you’re working with macOS Mojave and macOS Catalina, the top reasons of slow Mac performance may include:
- High CPU usage of apps. Using programs for video conversion, backup, 3D rendering, etc., require a large amount of processing power.
- Insufficient RAM. Some applications require more RAM than is currently available on the system. When the required RAM is not available, the computer constantly saves some of the data from memory to disk.
- Launching multiple applications simultaneously and having too many applications running in the background.
- Unnecessary browser tabs left open. Websites with lots of media files and animations can slow down your computer.
- Lack of free disk space. For normal operation, the system requires at least 20GB of free disk space to store temporary files.
- Apps that aren’t updated. Using outdated versions of applications may burden the system’s CPU usage.
- Not restarting regularly. A MacBook may run slowly if it has been running continuously for several weeks without rebooting.
- The possible use of Mac resources by malware, such as crypto miners.
- A damaged disk or using an outdated type of disk, for example, using HDD as a system one.
How not resolving a slow Mac can cause harm
If the reasons for Mac’s system slowdown aren’t addressed, its speed will decrease even more. This may lead to involuntary reboots of the Mac and the loss of user data.
You can download MacCleaner Pro – a special tool to fix a slow Mac quickly or safely. Or follow our guide to manually diagnose why your Mac is so slow and improve its performance.
How to fix a slow Mac
Detect and close memory-consuming apps
If your Mac is running slowly, the problem can be with a particular application. Every application utilizes system resources, so the more apps you have running, the slower your Mac. Moreover, a specific app can require too much CPU and memory.
Follow these steps to identify memory-consuming apps that are causing a system slowdown:
- Launch Activity Monitor.
- Click View in the Menu Bar and select Windowed Processes.
- Click the CPU tab find and select the apps that take up too much CPU usage.
- Click the Close (X) button to stop it.
- Then switch to the Memory tab.
- Find the apps that use too much memory and click the X button to stop them.
If you notice that your Mac is slowing down even when you launch a few apps, then your system needs more free RAM to perform the tasks. Clearing inactive RAM will help to improve your Mac’s performance.
The easiest way to free up RAM is to restart your Mac. Many users do not finish work on their Mac by the end of the day, but just put it into Sleep Mode. In this case, huge temporary files are created. Restarting a Mac allows your system to finish all system processes correctly, flush RAM, and clear temporary files. Also, you should shut down your Mac if you do not plan to use it for several days.
However, restarting Mac to free up RAM is certainly not convenient, since it interrupts your work.
Another option to clear RAM is using the Terminal command line.
- Open Terminal.
- Paste the command sudo purge and press Enter.
- Enter your admin password and again click Enter. Your RAM memory will be cleared.
- Run MacCleaner Pro.
- Click on the Performance category or go right to the Speed up Mac section from the sidebar.
- Select to Free up RAM and click on Speed up button.
- Then you will need just to confirm performing this task.
MacCleaner Pro also comes with an additional helping tool Memory Cleaner, which can automatically clean up RAM each time your system is out of RAM.
If you need to regularly work with heavy programs on your Mac, you had better increase your RAM; but first, check if it is possible to add more RAM to your computer:
- Go to the Apple Menu → About This Mac → Overview. Here you will find the information about your memory.
- Switch to the Support tab and click Specifications. It will open the Apple Support webpage with the information about RAM. Find the Memory section and check whether it can be configured on your computer.
*Read the guide on how to install more RAM to your iMac.
Update your software
Update the macOS system and all used applications. As a rule, developers create and optimize their applications for the latest version of macOS. If your Mac starts to run very slowly when you launch a specific application, it’s likely the app is not compatible with your system. Check the system requirements for the app, minimum processor speed, minimum RAM, recommended GPU card and so on. Update your apps to make them compatible with your new macOS.
Follow the steps below to check for macOS updates:
- Click System Preferences.
- Select Software Update.
- Click Update Now if a new update is available for your Mac.
To update apps downloaded from the App Store, do the following:
- Open App Store.
- Switch to the Updates tab.
- Click on Update All.
Disable startup programs
Having your favorite programs launch on startup is convenient. However, the more the programs running automatically at login, the slower your Mac startup.
You should disable all login items to make your Mac run faster.
- Go to System Preferences → User & Groups → Login Items.
- Uncheck and delete apps from the list of Login Items.
In this case, you can use a special tool from the MacCleaner Pro bundle – App Cleaner & Uninstaller. This app allows you to easily stop all the programs from launching on startup and even remove app extensions.
- Launch App Cleaner & Uninstaller and go to the Startup Programs section from the sidebar.
- Preview all startup programs on your Mac, especially the Launch agents and Login items sections. Disable or remove unneeded items to stop apps from running automatically when you log in.
Check your Mac for malware apps
It may happen that your Mac is working slowly because it is being affected by malicious software. Your Mac can receive malware when you download email attachments from unfamiliar senders or apps from untrusted websites.
*Read our previous article How to remove malware from a Mac.
To protect your Mac from malware, first check your security settings:
- Select System Preferences and click on Security & Privacy.
- Switch to the FileVault tab and turn it on.
- Then go to the FireWall and also turn it on.
Check hardware when Mac is slow
Another possible reason for a Mac slowdown is damage to or malfunction of the system drive. Use the Disk Utility app to find and solve possible storage issues.
Here is how to check the Mac startup disk for issues:
- First, you need to restart your Mac in Recovery mode. Turn your Mac off and restart it by pressing and holding the Command+R keys.
- Release the keys as soon as you see a startup window.
- Enter your password if needed and click Continue.
- Select the Disk Utility section to repair errors on your startup disk in the Utilities window that appears.
- Click on the First Aid button and click Run to check your disk for errors.
- If everything is okay, you will see the message that the process is complete, and some errors are fixed. If the operation failed, your disk probably has physical damage and needs to be replaced. Use this information to know how to repair your Mac.
Manage storage to make your Mac run faster
Often a MacBook or iMac runs slowly because there is no free space on the startup disk. If there is a shortage, the system has nowhere to store the temporary files and operate correctly. For stable Mac performance, at least 10% of free space is required. This means that you should clean up Mac storage and recover more free space.
To check how much storage space you have, go to the Apple Menu → About This Mac → Storage.
You can click Manage to see what types of data take the most space and decide what to remove. However, this report does not give a lot of information and only suggests that you will have to free up disk space by deleting files manually, one by one.
We recommend using the MacCleaner PRO, which provides a similar report on disk usage, and immediately provides tools for clearing each category of junk and user files.
Clear junk files
Your Mac stores lots of junk files, such as application caches, logs, language resources and so on. Individually these files may occupy only a few kilobytes, but all together they will consume gigabytes.
Manually finding and removing caches and other service files on a Mac is not easy. Here is how to quickly and safely clean up junk files on your Mac with MacCleaner Pro:
- Launch MacCleaner Pro.
- Click to clean up junk files.
- Select all unneeded types of junk files.
- Click on Clean up and confirm the removal.
Delete old and large files
You should optimize your disk usage and stop storing bulky content on your Mac hard drive. Recovering some free space will make your Mac run faster. Use the Disk Expert tool from MacCleaner Pro to analyze your disk space usage, discover large and old files and easily operate them.
- Launch Disk Expert.
- Scan your Macintosh HD.
- Review the diagram and find large and not used files.
- Remove large items or move them to an external storage.
Remove duplicate files
If, after analyzing your disk space usage, you are going to move your bulky data to external storage, we recommend that you first check your storage for duplicate files.
You can find duplicates manually. However, the best way to find and remove duplicate files on a Mac is to use a special tool from MacCleaner Pro – Duplicate File Finder. This tool automatically finds duplicate photos, videos, documents, and any other type of duplicate files. You can even find and clean up similar photos and similar folders.
Here is how to remove duplicates and get more Mac storage:
- Launch Duplicate File Finder from MacCleaner Pro.
- Add folders and scan them.
- Select duplicate files and click to remove them.
Uninstall unused apps
You may have many apps that you haven’t used for a long time. You should take a look at all your apps you installed for some earlier tasks, and remove the ones you no longer need. To quickly and completely remove apps from your Mac, use a special tool from MacCleaner Pro – App Cleaner & Uninstaller.
- Launch App Cleaner & Uninstaller.
- Select unneeded apps.
- Click to Uninstall them.
Now you know all the reasons why your Mac may be running slow and how to optimize its performance. You can fix these issues manually or use MacCleaner Pro, which will keep your Mac clean and free from unneeded apps, extensions, duplicates and malware files.
The MacCleaner Pro software is an all-in-one solution that allows you to safely clean up and speed up your Mac.