Mac System Has Run Out of Application Memory — How to Fix It

What Does This Error Mean?

Your Mac ran out of RAM — the fast memory apps use while running. When RAM fills up, macOS starts using your hard drive as a substitute, which is much slower. Closing apps and tabs frees up memory immediately.

Affected Models

macOS Sequoia
macOS Sonoma
macOS Ventura
macOS Monterey

Common Causes

Too many apps are open at the same time
A browser has dozens of tabs open, each using its own memory
One app has a memory leak and is consuming RAM it isn't releasing
The Mac doesn't have enough RAM for the tasks being performed
Background processes or startup apps are quietly consuming memory

How to Fix It

Click Force Quit in the warning dialog and close the app using the most memory.

The warning usually names the app that is causing the problem.
Open Activity Monitor (find it with Spotlight — press Command + Space and type Activity Monitor).

Click the Memory tab to see which apps are using the most RAM.
Quit any apps you are not actively using by selecting them in Activity Monitor and clicking the X button.

Browser tabs, video editing apps, and virtual machines are common memory hogs.
Reduce the number of browser tabs open. Each tab in Chrome or Firefox uses separate memory.

Safari is generally more memory-efficient than Chrome on Mac.
Restart your Mac to completely clear memory and start fresh.

After restarting, do not re-open all the same apps at once.

When to Call a Professional

You shouldn't need professional help for this. If your Mac shows this warning constantly even with just a few apps open, the RAM may be faulty.

Frequently Asked Questions

What is swap memory and is it bad?

Swap memory is when macOS uses your SSD as extra RAM. It works but is slower than real RAM. If your Mac is constantly swapping, you either need more RAM or need to run fewer apps.

Can I add more RAM to my Mac to fix this?

On older Intel Macs, some models allow RAM upgrades. On Apple Silicon Macs (M1, M2, M3, M4), RAM is built into the chip and cannot be upgraded. If you frequently run out of memory, consider a Mac with more unified memory.

Which apps use the most memory on a Mac?

Chrome, Slack, video editing apps, and virtual machines are the biggest users. Open Activity Monitor and click the Memory column to sort by usage. Quitting just one or two heavy apps often frees up a huge amount of memory.