How to free memory (RAM) from a Mac

October 19, 2022

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Are you experiencing slow Mac performance? A program has hung. Did you see a “Your system has run out of application memory” message or the dreaded spinning beach ball? All these signs can indicate that your RAM (or memory), is running at its maximum. Learn how to clear RAM from your Mac. Also, there are helpful tips that will help you optimize or clean up your Mac memory.

What is RAM?

First a quick primer. RAM is Random Access Memory. It stores data for ongoing tasks and processes. The difference between the RAM and the rest of the storage on your Mac is that it’s faster, therefore your Mac is designed to keep certain things in RAM in order to speed things up.

Most Macs ship with 8GB RAM or more – it’s been a long time since Apple shipped Macs with 4GB RAM or less. 8GB RAM should be plenty if you don’t run memory hungry applications and games, but even the most average user can come up against RAM issues due to memory hogging processes associated with badly designed web pages and apps. You can also find a separate article about RAM issues. How to determine how much RAM you have in your Mac .

What is Unified Memory?

Now that Apple is producing its own processors – the M1 and M2-series of chips – the company no longer uses RAM in the traditional sense. Instead all Macs with Apple’s own silicon inside use Unified MemoryThis information is shared between hardware components.

This means that M1 and M2-series Macs have memory as part of their architecture. There’s no memory slot or slots on the motherboard, nor is there an area where a memory chip has been permanently soldered on. Instead, the memory and chip are integrated into the same package.

This is why you should ensure you have enough memory for your Mac when you purchase it. It cannot be upgraded. It’s Your new M1 and M2 Macs probably need a cleaner appThere are many options, which we will discuss further below.

Unified Memory does have some benefits. Because the memory is accessible by both the CPU and GPU it can be allocated where it’s needed, and there is no performance hit because swapping from one to the other is instant and there is no need to copy data over as it’s instantly accessible. This means it is more efficient and should bring you speed benefits.

This should mean that 8GB RAM in a M1 Mac isn’t the same as 8GB RAM in an Intel Mac. But we still advise that you get the maximum amount of RAM you can afford when you buy a new Mac – you can do so as a build to order option at point of purchase. The Mac Studio allows you to choose from 16GB RAM up to 128GB.

You shouldn’t actually need 16GB or more RAM unless you use really power hungry apps. 8GB should suffice for normal use.

Do I need more RAM?

You may have problems if your Mac uses the majority of RAM.

Performance issues
Spinning beach ball
‘Your system has run out of application memory’ message
Typing lag
Apps not responding or freezing, and apps crashing or freezing
Apps and web pages take ages to load

These might be the problems you are experiencing.

If you have an old Mac and it is possible to upgrade the RAM this might be the solution you need, but we suspect that the RAM in the majority of our readers’ Macs can’t actually be updated. We have already mentioned that you cannot update the Unified Memory if your Mac is an M1-series, M2-series processor.

But, even if it is possible to add more RAM to your Mac there might be a much simpler solution, so we’d suggest that you try some of the tips below before rushing out and buying more RAM.

Of course if it’s more RAM you want, and you can add more RAM to your Mac, then read How to upgrade RAM on a Mac. Also, read How to determine how much RAM your Mac has

How to clear the memory on a Mac

If installing more RAM isn’t an option – or you want to attempt to fix the problem first – what can you do to address your Mac RAM problem?

One option is to use an app to clear your Mac’s RAM (or Unified Memory). We will be discussing a few of these options at the end. If you’d prefer to jump to that section click here: These are the best apps to clear Mac RAM

However, before you install more RAM, or resort to downloading an app, there are a number of things you can do that might free up your RAM and fix your Mac’s memory problems.

Step 1. Step 1.

The simplest way to clear RAM is to restart your computer. There’s a reason why the IT desk always tells you to “turn it off and on again!” Most of the time that will solve your problem. (See: Do I need to shut down my Mac at night?)

The RAM and disk cashes will be empty when your Mac restarts. You should notice a smoother start to things once again.

It may be difficult to restart your Mac. Perhaps your system has hung and you are afraid of losing unsaved information, perhaps and the idea of closing and reopening umpteen apps doesn’t appeal, or maybe you are in the middle of something that you don’t want to interrupt (even if that is the process that is stealing all the RAM).

If you don’t want to restart your Mac what can you do to free up RAM? Read on…

Step 2. Step 2.

This also might not be something you want to do if your Mac is hung and you are in the middle of something, but it’s a good option to try necause it’s possible that your problem is related to a known issue with macOS. This is why it’s always worth checking to see if you are running the most up to date version of the OS, and updating it if necessary.

Apple releases frequent updates with bug fixes, which might solve your problem.

We cover How to update the operating software on your Mac separately.

Step 3. Check Activity Monitor

Activity Monitor is the first place to go when your Mac freezes or slows down. Activity Monitor comes as an app with your Mac. It can be found in Utilities or you can start typing Activity Monitor into Spotlight (press Command + Space) to open a Spotlight window.

Activity Monitor will display how much memory is being used. It will also help you identify which apps are using more resources than they should.

You’ll be able to see how your memory is being used in the Activity Monitor window. You’ll see details about each process and app, such as the amount of memory, how many threads, and so on. By right-clicking on one column header, you can see additional columns like Energy Impact, which is useful if your battery power is low.

If you select the Memory tab, as well as details about how much memory each process is taking up, you’ll see a graph for Memory Pressure, and data about Physical Memory, Memory Used, Cached Files, Swap Used. Below that, you’ll find sections for App Memory, Wired Memory or Compressed.

As for what that all means, App Memory is what’s actually being used by apps and processes, Wired memory is what’s been reserved for apps and can’t be freed up, and Compressed is inactive memory that can’t be used by other apps. All of this will add up to the Memory Used number.

Cached Files is the amount of unassigned storage that you have. (If you are wondering what Swap Used is, it’s the memory being used by macOS, so it’s already accounted for in the Memory Used calculation).

The Memory Pressure section will show you a graph which gives you an overview of the pressure in your system. It should be green. However, if you don’t have enough memory, the graph may turn yellow or red. Even if you have plenty of memory, it is possible for the graph to be red. This could indicate that there are problems.

Activity Monitor: How to Free Up RAM

Open Activity Monitor.
Click on Memory to open it.
To sort processes by memory usage, click the Memory column. This will allow you to easily see which app or process is using up RAM.
After you have identified a suspect application, select it and click Information (i) in your menu. This will give you information about what’s happening and the amount of memory used by this particular process. To quit this app, click on Quit.
After you click Quit, you will be prompted to confirm that you want to close this window. Cancel, Force Quit, or Quit. Force Quit is useful in cases where the app has been frozen.
You can also close a process quickly by selecting it from Activity Monitor, then clicking the X to force it to quit. This doesn’t necessarily close the app. If it’s a web page causing issues rather than quit your browser it will just close and reload that page. But if you were to quit a Photoshop process the application itself will close (and you’ll probably see a ‘closed unexpectedly’ warning.

Note: You shouldn’t close a process if you don’t know what it is as it may be required by your Mac.

Step 4. Step 4.

If you glanced at Activity Monitor and noticed that certain apps appeared to be hogging resources even though you weren’t using them – maybe you didn’t even realise they were running, you may benefit from closing them down.

Even if you don’t look in Activity Monitor, a quick glance at your Dock could identify a few running apps that you could quit, thereby freeing up some resources. If you look at the Dock you’ll notice that some apps have a dot below their icon – these apps are open.

How to close an Application

Right-click the icon of the app in the Dock.
Click on Quit.

Step 5. Step 5.

In terms of suspect apps, it’s not always just the RAM that’s being hogged by an app. Sometimes, an app may be using too much processing power which can slow down things.

Activity Monitor: How do you check CPU usage?

Open Activity Monitor.
Click on the CPU tab.
Click on the column header to sort the processes by %CPU.
Look for abnormal usage – if an app or process is using a high percentage of CPU it’s probably what is causing the issues.
Click on the (x), in the menu to quit the app.

It is possible that a kernel_task runs in the background, consuming a lot of resources. If that is the case you won’t be able to kill that process – this is because a kernel_task represents a collection of operating system processes. Restarting your Mac is the only way to stop a Kernel_task. It is possible that the problem with Kernel_Task may be related to a hardware issue. If this happens, you might continue to see the same problem. If this is the case, you may want to As described here, run an Apple Hardware Test.

Step 6. Step 6.

Are you sending anything to print lately? It’s possible that a big print job is queued up and that has caused your Mac to hang.

Step 7. Step 7.

We don’t recommend this unless you are an advanced user, but you could try opening Terminal and typing in: sudo purge. Next, enter your password and wait until inactive memory is cleared.

How to decrease RAM usage on a Mac

Below you’ll find solutions to problems with your Mac’s memory. But how can you prevent that from happening?

If you are struggling because your Mac doesn’t have a lot of RAM then there are a few things you can do to maximise what is available. This could also be helpful
Accelerate your Mac.

Step 1. Tidy up Your Desktop

If your Desktop is cluttered with documents, images, screenshots and the like, it’s worth tiding it up – or at least dragging everything into a folder. This is because macOS treats every icon on your Desktop as if it’s an active window, therefore the more icons you have littered around your Desktop the more memory will be used. Most things are saved to your Desktop automatically, so clearing out your Desktop is a matter of taking a few minutes to do a little bit of cleaning up.