macOS Startup Key Commands

One of the features of macOS is the ability to issue commands during the startup of the  macOS to perform specific operations or evoke different startup states. In order to issue the commands associated with the different key combinations, the key combinations must be pressed at the moment the startup chime sound is heard and the screen changes color from black to grey on system startup and held until the desired operation occurs.

Please note that these key combinations only work on Macs with Intel processors. For newer Macs with Apple Silicon chips, follow this guide to access different startup options: https://support.apple.com/guide/mac-help/macos-recovery-a-mac-apple-silicon-mchl82829c17/mac

• Option - Display all bootable volumes (Startup Manager)
• Shift - Perform Safe Boot (start up in Safe Mode)
• C - Start from a bootable disc
• T - Start in FireWire target disk mode
• X - Force Mac OS X startup (if non-Mac OS X startup volumes are present)
• Command-V - Start in Verbose Mode
• Command-S - Start in Single User Mode
• Mouse button - Force eject CD/DVD

More information about macOS key commands are available on the Apple website:
http://support.apple.com/kb/HT1343

More startup key-command information:
https://support.apple.com/en-us/HT201255