Start up in safe mode
On a Mac with Apple silicon, the steps are the same on macOS 15 Sequoia, macOS 26 Tahoe and macOS 27 (Apple, macOS 15; macOS 27):
- Choose Apple menu › Shut Down, and wait until the screen is black and any lights are off.
- Press and hold the power button (the Touch ID button on a MacBook) until Loading startup options appears.
- Select your startup disk, usually Macintosh HD.
- Press and hold Shift, then click Continue in Safe Mode. The Mac restarts by itself.
- Log in as usual.
On an Intel-based Mac, Apple's steps differ: turn it on or restart it, immediately press and hold Shift until the login window appears, then log in; you may be asked to log in twice (Apple, Start up your Mac in safe mode).
Check that it worked
The login window shows Safe Boot in red at the top right of the screen. Once you're logged in, there are two other ways to check:
- System Information: hold Option, choose Apple menu › System Information, click Software in the sidebar and look at Boot Mode. It reads Safe in safe mode and Normal otherwise.
- Terminal: the same line, read-only and with no password needed.
system_profiler SPSoftwareDataType | grep "Boot Mode"On our MacBook Pro with macOS 27.0.1, started normally, it printed Boot Mode: Normal.
What safe mode does
Apple describes three things (Apple):
- It stops certain software loading at startup: login items, extensions macOS doesn't need, and fonts that macOS didn't install.
- It runs a basic check of the startup disk, a lighter version of First Aid in Disk Utility.
- It clears some system caches, including font caches and the kernel cache, which macOS rebuilds as needed. Apple notes this can temporarily free some storage.
Your documents, apps and settings aren't touched. Some things work differently while you're in safe mode, though: Apple lists video capture, graphics performance, file sharing, Wi-Fi, accessibility features, audio devices and devices connected over USB or Thunderbolt as possibly not working as expected. So a choppy screen or a missing external device in safe mode isn't a new problem, and it isn't the moment to judge your Mac's speed.
When it's worth trying
Safe mode is a test more than a fix. It's worth the restart when the problem could come from something that loads at startup:
- The Mac is slow from the moment you log in, or slow everywhere after you installed something. Run the checks in Why is my Mac so slow? first; safe mode is the step after them.
- An app or the whole Mac freezes soon after login, or a pop-up from a helper keeps appearing. Mac frozen or stuck on the spinning wheel? covers the immediate recovery.
- The Mac restarted with a problem message after you added software or a driver.
- kernel_task or the fans run hard while the Mac is idle and cool, where safe mode helps rule out startup software before you look at hardware (What is kernel_task?).
It won't help with a problem that's in a document, a website or an app you open yourself after logging in. For those, start with the app.
What the result tells you
Use the Mac in safe mode for as long as it normally takes the problem to appear, then restart normally and compare. Apple's own reading of the result:
| In safe mode | After a normal restart | What it points to |
|---|---|---|
| Problem gone | Still gone | Fixed by the disk check or the cleared caches. Nothing more to do |
| Problem gone | Back again | A login item or other software that loads at startup |
| Problem still there | Still there | Not startup software. Apple suggests reinstalling macOS, which keeps your files; consider hardware too |
Source: Apple, Start up your Mac in safe mode.
Find the login item responsible
If the problem only happens in a normal startup, narrow it down:
- Remove login items. Open System Settings › General › Login Items & Extensions. Remove apps under Open at Login, and switch off helpers in the background list (Allow in the Background on macOS 15, App Background Activity on macOS 26 and 27). Restart and test. Switch things back on a few at a time until the problem returns; how to stop apps opening on startup covers the helpers that list doesn't show.
- Try a new user account. Apple suggests adding one in System Settings › Users & Groups and logging in to it for testing. It has none of your startup software or settings, so if the problem doesn't happen there, the cause lives in your own account.
- Update or remove the culprit. Once you've found it, check for an update from the developer, or leave it switched off if you don't need it.
If the problem continues in safe mode
Then the cause isn't the software safe mode switches off. Apple's next step is to reinstall macOS from macOS Recovery, which doesn't remove your apps or personal data, though a backup first is still wise (Apple, How to reinstall macOS). It's also worth ruling out hardware: how to run Apple Diagnostics covers the test on macOS 15, 26 and 27. And if the Mac is restarting on its own rather than misbehaving, what to do when your computer restarted because of a problem is the better starting point.
Leave safe mode
Choose Apple menu › Restart without holding any keys (Apple). The Mac starts up normally, with your login items back. There's nothing to undo: the caches safe mode cleared are rebuilt as macOS needs them.
How Tend helps
Safe mode tells you that startup software is involved, but not which piece. Tend's free Startup Items view lists the launch agents and daemons on your Mac with the app or vendor that installed each one, including helpers System Settings names only by developer, and switches them off and on again reversibly, so you can test one at a time without hunting through Library folders.
Questions
How do I start my Mac in safe mode with Apple silicon?
Shut down. Press and hold the power button until Loading startup options appears, select your startup disk, then press and hold Shift and click Continue in Safe Mode. The Mac restarts; log in as usual. The steps are the same on macOS 15, 26 and 27.
How do I know if my Mac is in safe mode?
The login window shows Safe Boot in the menu bar. Once you're logged in, hold Option, choose Apple menu › System Information, click Software, and check Boot Mode: it reads Safe in safe mode and Normal otherwise.
How do I get out of safe mode on a Mac?
Choose Apple menu › Restart, without holding any keys. The Mac starts up normally. Nothing you did in safe mode needs undoing.
Why is my Mac slow in safe mode?
Apple says some features may not work as expected in safe mode, including graphics performance, and safe mode clears some system caches that macOS then rebuilds. Judge whether your problem goes away, not how smooth the animations are.
Does safe mode delete anything?
Not your files or settings. Apple says safe mode clears some system caches, such as font caches and the kernel cache, which macOS creates again as needed, and runs a basic check of the startup disk.
Related guides
Mac maintenance on Apple silicon: what still matters
Targeted fixes, and when each one helps
Why is my Mac so slow? How to find the cause and fix it
The checks to run before safe mode
How to stop apps from opening on startup on a Mac
Switch off the login items safe mode skips
What is kernel_task on Mac, and why is it using so much CPU?
When safe mode helps narrow down heat
Sources
- Apple, Start up your Mac in safe mode (5 December 2025)
- Apple, Start up your Mac in safe mode (Mac User Guide): macOS 15, macOS 26, macOS 27
- Apple, How to reinstall macOS
- Apple, Change Login Items & Extensions settings on Mac: macOS 15, macOS 26, macOS 27
system_profileroutput from our MacBook Pro (M2 Max) with macOS 27.0.1, 20 October 2026
See everything that loads when your Mac starts
Tend is free to download. Pro is $1.99 a month, $12.99 a year with a 7-day free trial, or $29.99 once.