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Why your Mac is so slow: 3 reasons

"Why is my Mac so slow?" we hear you say to yourself. Stay right where you are if you want to get some great tips from those who really know. Let's kick off with 3 of them - plus something extra.

A full hard drive

It could be you've had your Mac for a while now, or at least a couple of years or more - and you have the hard drive to show for it. Your Mac actually needs about 20% free hard disk to work its best.

If an issue is present, there's a way to be sure. Click on 'About This Mac' to open up a summary window of your Mac's memory, processor, graphics, and other features. Navigate the tabs at the top of this window and click 'Storage'. Once here, you can see an overview of your 'Macintosh HD' hard drive storage and which things are taking up the most space. Click 'Manage' to reveal some further helpful options, such as 'Empty Trash Automatically' and 'Reduce Clutter'.

No doubt Apple's in-built tools are helpful, but it's worth pointing out that CCleaner for Mac can help remove hidden, lurking cache and temporary files that can take up valuable space on your hard drive, possibly more than you realize. We think it's much easier than Mac's standard tool for cleaning files like these, especially because CCleaner can manage multiple aspects of your Mac's maintenance in one place. 

Software that's not up to date

Updates can sometimes feel like a nuisance, but they actually play a central role in fixing bugs in your computer software, plus any Mac security issues that might exist on your machine. Missed updates can slow down your Mac too; so if you're currently wondering "why is my Mac so slow", there's a chance this could be a cause, at least one of them anyway.

A good way to ensure you're doing regular updates is to visit the Mac App Store and click on 'Updates' within the App Store's toolbar. For a slightly simpler method, visit your Mac's 'System Preferences' and then go to the App Store settings. Here, you can set it so that it checks for new updates automatically or downloads them in the background once they become available. 

Too many startup programs

A Mac that's had a lot of use could also have a lot of apps installed. If you're also thinking "why is my Mac so slow when it starts up", it could be that a lot of these apps launch automatically each time this happens. Processes from these apps can run in the background and bog down your system performance as soon as you start your computer. Annoying - to say the least.

macOS gives you a tool to fix this yourself. To do this, go to your 'System Preferences' and then 'Users & Groups'. Find your username, click it and then go to 'Login Items'. If you've reached this stage, you should be able to identify and choose which apps you don't want to auto-launch each time you start up your Mac.

Something you might not know is that, again,  CCleaner for Mac provides an easy way to solve this problem too, among other handy features designed to help you out. Perhaps you can guess what the 'something extra' we mentioned, in the beginning, was referring to?

Try out CCleaner for Mac

Yes, there may be various helpful, built-in tools so you can look after your Mac, but having one simple, dedicated app that can manage unwanted startup programs and delete junk files to free up hard drive space is a much better long-term solution. That's why we built one. CCleaner for Mac does both these things as well as helping your Mac security by deleting internet files and passwords. It can also help with things like repairing disk permissions to help ensure the smooth operation of your computer.

So if you're looking for an answer to the question "why is my Mac so slow?" the good news is that CCleaner for Mac can help with this in addition to improving your security. Why not try it for free right now?


  • Why is my Mac so slow all of a sudden 2022?

    Every year, bigger and better apps come out, which take up more of your Mac’s resources. As your Mac gets older, it’s important to keep at least 20% hard drive space free, keep software up to date, and limit the programs that launch on startup.

  • Why is my Mac so slow after an update?

    While it doesn’t usually happen, an update can slow down your Mac. Here’s what to do: make sure all of your third-party apps are up to date, older Macs can also benefit from an upgrade to an SSD from an HDD. You can also speed up your Mac using our optimization app.

  • Why is my Mac suddenly extremely slow?

    Common reasons for a slow Mac are new, large apps installed that run in the background, missed software and operating system updates causing a miscommunication somewhere, and not enough free space on your Mac for it to perform tasks.