Check your RAM use in Activity Monitor, the built-in tool on every Mac

Open Activity Monitor by pressing Command + Space, typing "Activity Monitor", and pressing Enter. Click the Memory tab at the top. You will see a list of every program running on your Mac, how much RAM each one is using, and how much total RAM is available.

The number you want to watch is in the bottom right corner: "Memory Pressure". When it is green, your Mac has enough RAM for what you are doing. When it turns yellow or red, your Mac is running low and will slow down because it is using your hard drive as temporary memory — which is much slower than actual RAM.

Activity Monitor updates in real time, so you can watch what happens when you open a new program or browser tab. Close the window and your RAM use drops when ready.

Key Takeaways

  • Activity Monitor shows which programs are using the most RAM and whether your Mac has memory left over.
  • Memory Pressure in the bottom right tells you if your Mac is running low: green is fine, yellow or red means slowdown is coming.
  • Closing unused programs and browser tabs frees up RAM when ready and makes your Mac faster.
  • If Memory Pressure stays red even after closing programs, your Mac may not have enough RAM for what you do regularly.

What the Memory tab numbers actually mean

Activity Monitor shows several columns. The one labeled "Memory" is what each program is using right now. "Swap" is how much of your hard drive the Mac is using as backup memory — a high swap number means your Mac is struggling and will feel slow.

At the bottom of the window, "Physical Memory" shows your total RAM. "Memory Used" shows how much is in use. "Cached Files" is data your Mac is holding onto in case you need it again — it is not really "used" and will be cleared if another program needs the space. "Swap Used" is the hard drive memory we mentioned; the higher this number, the slower your Mac will run.

If your total Physical Memory is 8 GB and Memory Used is 7.5 GB, you are running tight. If Swap Used is also high, your Mac is definitely slowing down because it is writing to the hard drive constantly.

How to find which programs are eating your RAM

In Activity Monitor, click the Memory column header to sort by RAM use. The programs at the top are using the most. Safari and Chrome are often the biggest users, especially if you have many tabs open. Zoom, Slack, and email clients also use significant RAM.

If a program is using more RAM than you expect, you can force it to close by selecting it and clicking the X button in the top left. Your Mac will ask if you want to force quit. Say yes. The program will stop when ready and that RAM will be freed.

Do not force quit programs you are actively using — you will lose unsaved work. But if something is frozen or using RAM even though you are not using it, force quitting is safe and effective.

When to close programs to free up RAM

If Memory Pressure is green, you do not need to do anything. Your Mac is handling everything fine. If it turns yellow, close some programs or browser tabs. If it turns red and stays red, your Mac is struggling and you should close things until it improves.

Browser tabs are an straightforward place to start. Each open tab uses RAM, and some websites use more than others. Close tabs you are not reading. If you use Chrome, it typically uses more RAM than Safari, so switching browsers can help if you regularly run low.

If you regularly see red Memory Pressure even after closing programs, your Mac may not have enough RAM for your work. Upgrading RAM is possible on some older Macs but not on newer models. If you cannot upgrade, you may need to work with fewer programs open at once or consider a newer Mac.

The difference between RAM and storage space

RAM and hard drive storage are not the same thing. RAM is fast memory your Mac uses while programs are running. Storage is where your files live permanently. You can have plenty of storage space but run out of RAM, or vice versa.

If your Mac is slow but Activity Monitor shows plenty of green Memory Pressure, the problem is not RAM — it is probably storage space or something else. If Memory Pressure is red, RAM is the problem.

Checking RAM on older Macs running older macOS versions

Activity Monitor works the same way on every Mac and every recent version of macOS. Open it, click Memory, and look at Memory Pressure. The steps are identical whether you are on an M1 Mac, an Intel Mac, or a Mac from ten years ago.

If you are running macOS older than 10.7, Activity Monitor may look slightly different, but the Memory tab still shows the same information. The column names might be in a different order, but you are looking for the same numbers: how much RAM each program uses and what your total available RAM is.

Frequently Asked Questions

What is a normal amount of RAM to be using?

It depends on what you are doing. Browsing the web with a few tabs open might use 2 to 4 GB. Video editing or running virtual machines can use 8 GB or more. There is no "normal" — what matters is whether Memory Pressure is green. If it is, you have enough for what you are doing right now.

Why does my Mac use RAM even when I am not using it?

Your Mac runs background processes constantly: system updates, indexing files, cloud syncing. This is normal. The RAM will be freed up when a program needs it. Only worry if Memory Pressure is yellow or red.

Can I add more RAM to my Mac?

On older Intel Macs, yes — you can buy RAM and install it yourself or have someone do it. On newer Macs with Apple Silicon chips (M1, M2, M3), RAM is built in and cannot be upgraded. Check your Mac model and year to find out which applies to you.

Does restarting my Mac free up RAM?

Yes. Restarting closes all programs and clears all RAM, so your Mac starts fresh. If Memory Pressure is constantly red, restarting can help temporarily. But if it goes red again after a few hours, the problem is that you need more RAM or need to close programs more often.

Is high swap usage dangerous?

No, it will not damage your Mac. But it makes your Mac slow because the hard drive is much slower than RAM. If swap is high, close programs to free up RAM and the slowness will stop.