Safe Mode (or Safe Boot) is a special macOS boot mode that loads only the essential system components. Specifically, when you boot into Safe Mode, macOS does several things automatically:
| What safe mode does | Why it's useful |
|---|---|
| Checks the boot disk (fsck) | Automatically detects and repairs file system errors |
| Only loads Apple kernel extensions | Excludes third-party drivers that can cause conflicts or crashes |
| Disables opening elements | Applications launched at start-up are ignored |
| Disables custom fonts | Eliminates corrupted fonts that can block start-up |
| Clears certain system caches | Removes potentially corrupted caches (kernel caches, font caches, etc.) |
In short, Safe Mode isolates problems. If your Mac works normally in Safe Mode but crashes in normal mode, it means that a third-party extension, a boot item or a corrupted cache is responsible for the problem.
Safe mode is your first troubleshooting reflex in the following situations:
| Problem | What safe mode can solve |
|---|---|
| Mac stuck on Apple on startup | Bypasses an extension or driver blocking normal start-up |
| Mac very slow to start up | Identifies whether the slowdown comes from third-party start-up components |
| Repeated kernel panics | Isolates incompatible third-party kernel extensions |
| Screen frozen after connection | Bypasses problematic opening applications |
| Problem after installing software | Allows you to start up without the problematic software and uninstall it |
| Sudden deterioration in performance | Clears caches and identifies responsible third-party processes |
If your Mac won't boot at all (no sign of life, no sound, no light), Safe Mode won't help because it requires a minimal start-up. Instead, take a look at our Mac guide that won't turn on or our MacBook black screen guide.
The procedure is different on Apple Silicon Macs compared with Intel Macs. Here are the detailed steps:
1. Turn off your Mac completely. If the Mac freezes, hold down the power button for 10 seconds to force it to shut down.
2. Hold down the power button until you see the boot options (you'll see your boot disk and possibly the Options icon).
3. Select your start-up disk (usually «Macintosh HD»).
4. Hold down the Shift and click on «Continue in Safe Mode».
5. The Mac starts up. The process is slower than usual as macOS checks the disk and clears the caches.
On Intel Macs (all Macs before the end of 2020, plus certain 2020 models), the procedure is simpler:
1. Switch off your Mac completely.
2. Turn on the Mac and immediately hold down the Shift pressed.
3. Hold down Shift until you see the login screen. You will see the words «Booting without extensions» in red in the menu bar, confirming that you are in safe mode.
4. Log in with your usual password.
If you don't know whether your Mac is Intel or Apple Silicon, use our Mac identification tool or click on the Apple menu then «About this Mac»: if you see «Chip» followed by M1/M2/M3/M4, it's Apple Silicon. If you see «Processor» followed by Intel, it's Intel.
Several visual clues confirm that the Mac is indeed in safe mode:
On the connection screen, the words «Booting without extensions» appear in red in the menu bar (Intel Mac) or the text «Safe Mode» is displayed (Apple Silicon Mac).
Once you've logged in, you can check via the Apple menu: click on the Apple menu, then on «About this Mac», then on «System Report» (or hold down Option and click on «System Information»). In the sidebar, click on «Software». The «Startup Mode» line should read «Safe».
You'll also notice that the Mac is slower than usual, that some features are unavailable (no Wi-Fi on some models, no sound on others, no file sharing) and that the interface may look slightly different (no transparency effects).
Safe mode is not designed for prolonged use. It is a diagnostic and repair mode. Here are the actions to perform:
This means that the problem comes from a third-party component. The usual suspects are kernel extensions (antivirus, virtualisation software, VPN), startup elements (applications that launch when a session is opened) and corrupted caches.
Recommended actions:
Open System settings, then General, then Opening (or «Openers»). Deactivate all suspicious opening items, especially those you have recently installed. Restart normally (without holding down Shift). If the problem has disappeared, reactivate the elements one by one to identify the culprit.
A failure in Safe Mode suggests a deeper problem: corrupted file system, failing SSD or hardware problem. In this case, try macOS recovery (Cmd + R at boot on Intel, or power button held down then Options on Apple Silicon) to reinstall macOS or repair the disk with Disk Utility.
If recovery also fails, a macOS bootable USB key may be the solution, or a professional diagnosis in the workshop.
Leaving Safe Mode is simple: restart your Mac as normal. Click on the Apple menu, then «Restart», and don't hold down any keys during start-up. The Mac will then start up in normal mode with all the extensions and opening items.
If you have made changes in Safe Mode (deleting software, disabling boot items), they will be applied on normal restart.
Safe Mode is just one of the boot modes available on the Mac. Here are the other useful options for troubleshooting:
| Mode | How to get there | Usefulness |
|---|---|---|
| Recovery mode | Intel: Cmd + R on start-up. Apple Silicon: hold down the power button, then Options | Reinstall macOS, Disk utility, restore Time Machine |
| Internet recovery | Intel: Cmd + Option + R. Apple Silicon: automatic if local recovery not present | Download and reinstall macOS from Apple servers |
| Target Disk Mode | Intel: T at start-up. Apple Silicon: hold button, then Share Disk | Accessing the Mac disk from another Mac |
| Verbose mode | Intel: Cmd + V on start-up | Display system messages during start-up to identify errors |
| Apple diagnostics | Intel: D at start-up. Apple Silicon: hold button, then Diagnostics | Testing hardware (RAM, SSD, sensors, battery) |
| NVRAM reset | Intel only: Cmd + Option + P + R on start-up | Reset start-up, resolution and volume settings |
For a complete guide to resetting your Mac, see our Mac reset tutorial. If your Mac is slow to start up and use normally, our Mac optimisation guide offers 12 complementary solutions.
Safe Mode automatically deletes certain system caches (kernel, font and system library caches). Your documents, photos, applications and other personal files are never affected. These caches are automatically recreated at the next normal start-up.
Not always. Safe Mode only loads essential kernel extensions, and Wi-Fi requires specific extensions. On most recent Macs (Apple Silicon), Wi-Fi works in Safe Mode. On some Intel Macs with a third-party Wi-Fi card, it may be unavailable.
If the Mac doesn't start up in Safe Mode, the problem is probably hardware (faulty SSD, faulty RAM) or the file system is badly corrupted. Try recovery mode to repair the disk or reinstall macOS. If that doesn't work, a workshop diagnosis is recommended.
No. Safe Mode starts macOS with limited functionality, you can use the Finder and applications. Recovery mode loads an independent mini-system that allows you to reinstall macOS, use Disk Utility or restore Time Machine, but not use your normal applications.
Limited. You can browse the Internet, consult files and uninstall applications. However, certain functions are unavailable: Wi-Fi (sometimes), file sharing, DVD playback, iCloud and certain third-party applications. Safe Mode is for troubleshooting, not for prolonged use.
Longer than a normal boot. Safe Mode checks the disk and clears the caches, which adds 1 to 5 minutes to the usual boot time. On a Mac with a fast SSD, count on 2 to 3 minutes. On an older Mac with a hard disk, it can take up to 10 minutes.
Yes, in some cases. By clearing corrupted system caches, Safe Mode can resolve slowdowns caused by outdated or corrupted cache files. If the Mac is fast in Safe Mode but slow in normal mode, third-party software is causing the problem.
Yes, Safe Mode requires your usual session password. If you have FileVault (disk encryption) enabled, you may need to enter your password twice: once to unlock the disk and again to log in.
Yes, Safe Mode works on all Macs: MacBook Pro, MacBook Air, iMac, Mac mini, Mac Studio and Mac Pro. The procedure is identical, the only difference is Intel vs Apple Silicon.
If the problem also exists in Safe Mode, it is probably related to the macOS system itself or to the hardware. Try resetting NVRAM (Intel Macs), reinstalling macOS from recovery mode, or performing a hardware diagnostic (D key at startup). If nothing works, a professional diagnosis is the next step.
Over 15 years of Apple expertise in Brussels. Free, no-obligation quote and 180-day guarantee on repairs.
