Create a bootable installer for macOS

Do you need a bootable installer?

You don't need a bootable installer to upgrade macOS or reinstall macOS. However, a bootable installer can be useful when those or other macOS installation methods are unsuccessful, or when you want to install macOS on multiple computers without downloading the installer each time.

Download the full macOS installer

1. Get the full installer by downloading it via the App Store or your web browser using the download links and instructions in How to download and install macOS. Important:

   • You might need to download from a Mac that is compatible with the macOS you're downloading. If downloading an older macOS, you might also need to create the bootable installer on an older Mac that is compatible with it.

   • Download from a Mac that is using the latest version of OS X El Capitan, or any later version of macOS. Find out which macOS your Mac is using.

   • Enterprise administrators: Download from Apple, not a locally hosted update server.

2. Check the name of the installer after downloading it. It should be an app named Install [Version Name], such as Install macOS Sequoia. If it’s a disk image (.dmg) or package (.pkg) file, review the download instructions for details about how get the installer from these files.

3. Check the location of the installer. It should be in the Applications folder, which is the folder that opens when you choose Go > Applications from the menu bar in the Finder. Move the installer to this folder, if necessary.

Connect and rename your USB flash drive

1. Connect a USB flash drive or other secondary volume directly to your Mac.

2. Check the storage capacity of the flash drive. A 32GB flash drive has more than enough storage space for any macOS installer, and 16GB is enough for most earlier versions of macOS. If more space is needed, Terminal will let you know. When you create the bootable installer, this flash drive will be erased.

3. Change the name of the flash drive to MyVolume, which is the name expected by the Terminal commands below.

Use Terminal to create the bootable installer

1. Open Terminal, which is in the Utilities folder of your Applications folder. Or use Spotlight in the menu bar to find and open it.

2. Depending on which macOS you downloaded, drag within the scrollable area of one of these commands to select the full command. Then copy it and paste it into Terminal. Press Return to enter the command.

   • Sequoia: sudo /Applications/Install\ macOS\ Sequoia.app/Contents/Resources/createinstallmedia --volume /Volumes/MyVolume

   • Sonoma: sudo /Applications/Install\ macOS\ Sonoma.app/Contents/Resources/createinstallmedia --volume /Volumes/MyVolume

   • Ventura: sudo /Applications/Install\ macOS\ Ventura.app/Contents/Resources/createinstallmedia --volume /Volumes/MyVolume

   • Monterey: sudo /Applications/Install\ macOS\ Monterey.app/Contents/Resources/createinstallmedia --volume /Volumes/MyVolume

   • Big Sur: sudo /Applications/Install\ macOS\ Big\ Sur.app/Contents/Resources/createinstallmedia --volume /Volumes/MyVolume

   • Catalina: sudo /Applications/Install\ macOS\ Catalina.app/Contents/Resources/createinstallmedia --volume /Volumes/MyVolume

   • Mojave: sudo /Applications/Install\ macOS\ Mojave.app/Contents/Resources/createinstallmedia --volume /Volumes/MyVolume

   • High Sierra: sudo /Applications/Install\ macOS\ High\ Sierra.app/Contents/Resources/createinstallmedia --volume /Volumes/MyVolume

   • El Capitan: sudo /Applications/Install\ OS\ X\ El\ Capitan.app/Contents/Resources/createinstallmedia --volume /Volumes/MyVolume --applicationpath /Applications/Install\ OS\ X\ El\ Capitan.app

3. When prompted, type your administrator password and press Return. Terminal doesn't show any characters as you type.

   • If you get a message that the installer does not appear to be a valid installer application, delete the installer, use Disk Utility to repair your startup disk, then download the installer again.

   • If you get a message that the command was not found, make sure that you’re using the correct command and the installer is in your Applications folder and named Install [Version Name]. And if creating the bootable installer on a Mac that is using macOS Sierra 10.12.6 or earlier, append --applicationpath to the command, followed by the appropriate installer path, similar to what is shown at the end of the command for El Capitan.

4. When prompted, type Y to confirm that you want to erase the volume, then press Return. Terminal shows the progress as the volume is erased.

   • If you get a message that Terminal would like to access files on a removable volume, click OK to allow Terminal to proceed.

   • If Terminal can't erase successfully, use Disk Utility to erase the volume using Mac OS Extended (Journaled) format, then try again.

5. When Terminal says that the install media is now available, your USB flash drive should have the same name as the installer, such as Install macOS Sequoia.

6. Quit Terminal, eject the flash drive, and disconnect it from your Mac.

Use the bootable installer

Follow the appropriate steps based on whether you’re using the bootable installer on a Mac with Apple silicon. Your Mac must be connected to the internet so that the installer can get firmware and other information specific to this Mac model. If the macOS you’re installing is incompatible with your Mac, installation might not complete or your Mac might start up to a circle with a line through it.

Mac with Apple silicon