Mac Running Slow? Why It Happens & 5 Easy Ways To Fix It

Every computer runs slowly from time to time, but for some reason, it’s always more frustrating when it’s a Mac. Maybe it’s the “It just works” marketing slogan or the closed-off nature of the system. Either way, a slow Mac is nothing to shrug off. 

In this post, we’ll walk you through five solutions to some of the most common problems causing a slow-running Mac. 

1. Your hard drive is full

Being full is more common on hard disk drives (the Macs with a spinning disk of memory) than solid-state drives (Macs with flash memory, i.e., most Macs released in the last five years). Still, it can happen to any Mac or device that stores data. 

Your Mac’s hard drive is the component of your Mac that stores data. The more files and folders you have on your computer, the slower your Mac will run. Once your Mac is nearly full, it’ll start to run noticeably poorly.

To check if you’re running out of storage, click the logo in the top left of your screen, then click “About This Mac.” In the popup that appears, click storage to view your used storage. 

If you’ve used less than 80% of your storage, you can assume this is probably not the issue. But if you’re running out of storage, the solution is pretty straightforward. You can move files off your computer and onto an external storage device, like a flash drive, or delete unneeded ones.

2. macOS needs to be updated

Another reason your Mac may be running slow is that you’re running an outdated version of macOS. 

macOS is the software that runs your computer, and if it’s too far out of date, you may have a poorly optimized computer, where apps are being built for a version of macOS that you don’t have. 

Again, this is a pretty straightforward problem to solve. Just open System Preferences, click Software Update, and if you need to install a newer version of macOS, follow the prompts to install it. 

For some users, upgrading to the latest version of macOS may seem like a bad idea, as users don’t like jarring changes or unstable operating systems. Though macOS updates do occasionally have their bugs, most of these fears are carried over from Windows operating systems. Macs only update once a year, and most of the time, the update is minimal and mainly to your benefit. And it’s free!

3. Your hardware is outdated.

You could, of course, be having the opposite problem. You’re entirely up to date on macOS, but your Mac itself is too outdated to run the latest version of macOS.

This happens because each version of macOS gradually requires more horsepower from your computer. It has new features, better graphics, more apps, and stronger security, all of which can put a toll on outdated hardware. 

This problem is a little bit trickier to identify on your own, as you won’t know for sure that your hardware is the issue without a professional opinion. Still, there are a few things you can check that will give you a good idea of whether or not you’re due for an upgrade. 

First, the general upgrade cycle for a Mac is five years. This means that after five years is a good time to buy a new Mac, and after seven years, you can safely call your Mac “old”. Macs certainly last longer than other computers, and some people can get ten years of use out of a Mac, but they aren’t invincible against age.

Second, you can check your Mac’s RAM. As operating systems become more complex, the amount of RAM your computer needs to run smoothly increases. At the time of writing, 8GB of RAM is considered the minimum amount of RAM you should have. If you have less than this and are running the latest apps and macOS, this is probably the culprit. 

You can check your RAM by navigating to About This Mac on your computer and check memory. 

4. Too many apps are running in the background

Probably the most common issue causing a slow-running Mac is having too many apps running in the background. When an app is running in the background, it means that the app is running without opening a window. Sometimes this is useful. The menu bar extension Magnet, for example, runs in the background and allows you to snap windows into place. 

Other times, apps are running processes and services that you probably aren’t benefiting from. This takes up RAM and, if enough apps are running this way, can cause your Mac to slow down. 

To check the apps running in your background, press command + spacebar to pull up Spotlight Search, type Activity Monitor, and press return. This app monitors every app and service currently running on your Mac, from Safari to the service that runs your mouse cursor. 

You can also see how heavy the load is on your CPU by looking at the little box at the bottom of this window titled CPU LOAD. The taller the graph is in this box, the slower your Mac will run.

To see which apps are using the most CPU, click % CPU near the top left of the window. If you see a column of “0.0” beneath this column after clicking it, click it again. This should show you the apps using your CPU from the greatest usage to the least usage. 

If there are any apps you recognize that are using a significant amount of CPU and shouldn’t be, click on them in this list and then click the “X” inside an octagon in the top left of the window. This will force that app to stop running. You can keep doing this until the CPU LOAD box at the bottom of the screen starts to show less usage. 

5. You need to clear your RAM

Last but not least, it could be that your RAM is full of extraneous data and needs to be cleared. If you aren’t sure what RAM is, think of it like this: You have memories stored in your brain that you aren’t currently accessing, like the Alphabet Song. 

Now that you’re thinking of that song, however, and possibly singing it to yourself, it has moved into your short-term memory and will stay there until you think of enough things that you forget it, and your brain moves back into deep storage. 

On your computer, your hard drive is like your brain’s deep storage, and RAM is your short-term storage. However, if your RAM is processing too many files at once, it can fill up and start to slow your computer down. Clearing your RAM won’t delete any files you’ve saved, it’ll simply clear everything currently running, putting you back at peak performance. 

To clear your RAM, open the Terminal app and type (without the quotation marks) “sudo purge” and press return. The terminal will probably ask you for your password, which you’ll enter, and then it will clear your RAM. 

Still need a hand?

These are some of the most common issues that can cause a slow Mac, but this is by no means an exhaustive list. If none of these solutions have resolved your issue, it may be time to bring your Mac to the experts. For all of your repair needs, you can reach out to ScreenWorks and receive the best care available. 

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