Under the pop-up menu, you'll see Select the OS X installer. (macOS used to be called OS X.) If you have only the Catalina installer on your Mac, Install Disk Creator will automatically select it. How to create a bootable macOS High Sierra installer drive Put the macOS High Sierra installer on an external USB thumb drive or hard drive and use it to install the operating system on a Mac. Make sure the drive is formatted for OS X Extended (Journaled). If it isn't, open up Disk Utility and format is so it is. Before you do so, back up any important data on that drive. The simplest way to create a boot USB drive is to download DiskMaker X and use it to create your drive. Generally, the latest version supports only the latest version of macOS; if you want to install something older than macOS High Sierra, check the list of older versions and download one that's compatible with your chosen operating system. There are two ways you can install OS X on to your external hard disk: by reinstalling OS X from the OS X Utilities repair screen or by downloading OS X from the App Store and running the installer. I'll show you both methods in case one isn't working for you. The easiest way is to download OS X from the App Store.
These advanced steps are primarily for system administrators and others who are familiar with the command line. You don't need a bootable installer to upgrade macOS or reinstall macOS, but it can be useful when you want to install on multiple computers without downloading the installer each time.
What you need to create a bootable installer
- A USB flash drive or other secondary volume, formatted as Mac OS Extended, with at least 12GB of available storage
- A downloaded installer for macOS Big Sur, Catalina, Mojave, High Sierra, or El Capitan
Mac Os To Usb
Download macOS
- Download: macOS Big Sur, macOS Catalina, macOS Mojave, or macOS High Sierra
These download to your Applications folder as an app named Install macOS [version name]. If the installer opens after downloading, quit it without continuing installation. To get the correct installer, download from a Mac that is using macOS Sierra 10.12.5 or later, or El Capitan 10.11.6. Enterprise administrators, please download from Apple, not a locally hosted software-update server. - Download: OS X El Capitan
This downloads as a disk image named InstallMacOSX.dmg. On a Mac that is compatible with El Capitan, open the disk image and run the installer within, named InstallMacOSX.pkg. It installs an app named Install OS X El Capitan into your Applications folder. You will create the bootable installer from this app, not from the disk image or .pkg installer.
Use the 'createinstallmedia' command in Terminal
- Connect the USB flash drive or other volume that you're using for the bootable installer.
- Open Terminal, which is in the Utilities folder of your Applications folder.
- Type or paste one of the following commands in Terminal. These assume that the installer is in your Applications folder, and MyVolume is the name of the USB flash drive or other volume you're using. If it has a different name, replace
MyVolumein these commands with the name of your volume.
Big Sur:*
Catalina:*
Mojave:*
High Sierra:*
El Capitan:
* If your Mac is using macOS Sierra or earlier, include the --applicationpath argument and installer path, similar to the way this is done in the command for El Capitan.
After typing the command:
- Press Return to enter the command.
- When prompted, type your administrator password and press Return again. Terminal doesn't show any characters as you type your password.
- When prompted, type
Yto confirm that you want to erase the volume, then press Return. Terminal shows the progress as the volume is erased. - After the volume is erased, you may see an alert that Terminal would like to access files on a removable volume. Click OK to allow the copy to proceed.
- When Terminal says that it's done, the volume will have the same name as the installer you downloaded, such as Install macOS Big Sur. You can now quit Terminal and eject the volume.
Use the bootable installer
Determine whether you're using a Mac with Apple silicon, then follow the appropriate steps:
Apple silicon
- Plug the bootable installer into a Mac that is connected to the internet and compatible with the version of macOS you're installing.
- Turn on your Mac and continue to hold the power button until you see the startup options window, which shows your bootable volumes and a gear icon labled Options.
- Select the volume containing the bootable installer, then click Continue.
- When the macOS installer opens, follow the onscreen instructions.
Intel processor
- Plug the bootable installer into a Mac that is connected to the internet and compatible with the version of macOS you're installing.
- Press and hold the Option (Alt) ⌥ key immediately after turning on or restarting your Mac.
- Release the Option key when you see a dark screen showing your bootable volumes.
- Select the volume containing the bootable installer. Then click the up arrow or press Return.
If you can't start up from the bootable installer, make sure that the External Boot setting in Startup Security Utility is set to allow booting from external media. - Choose your language, if prompted.
- Select Install macOS (or Install OS X) from the Utilities window, then click Continue and follow the onscreen instructions.
Learn more
For more information about the createinstallmedia command and the arguments that you can use with it, make sure that the macOS installer is in your Applications folder, then enter the appropriate path in Terminal:
- Big Sur: /Applications/Install macOS Big Sur.app/Contents/Resources/createinstallmedia
- Catalina: /Applications/Install macOS Catalina.app/Contents/Resources/createinstallmedia
- Mojave: /Applications/Install macOS Mojave.app/Contents/Resources/createinstallmedia
- High Sierra: /Applications/Install macOS High Sierra.app/Contents/Resources/createinstallmedia
- El Capitan: /Applications/Install OS X El Capitan.app/Contents/Resources/createinstallmedia
A bootable installer doesn't download macOS from the internet, but it does require an internet connection to get firmware and other information specific to the Mac model.
Ever since the release of Mac OS Lion the software upgrades for Macintosh computers are distributed through the online app store. Be it a clean install or upgrade, mac app store require you connect to the internet to download whole installation files. The online OS update is okay if you have stable broadband connectivity and enough bandwidth. Apple also provides an option for internet recovery of macOS if your computer fails to boot. But there are situations where you can't download the OS from the Apple servers. Having a bootable macOS offline installation disk is the only solution in such scenarios.
How To Make Mac Os X Install Usb
How to make a macOS bootable USB installer
It is possible to create a backup macOS installer on a DVD or USB drive but later is the best choice. Most of the Macs these days don't have DVD slots, and the installation through a disc is very slow. Hence we discuss only about making macOS recovery installer on a USB disc. For this you need a Mac and a USB pen drive of at least 8 GB space, and a third-party app called DiskMaker.
- First, download a copy of Disk Maker from the official website.
- Choose a version as per your requirement. For example, if you want make USB installer for macOS Catalina 10.15, download Disk Maker X 9.
- I use an MacBook Pro with High Sierra. Hence, I'm downloading disk maker X 7.
- The next step is to download full macOS installer from the App Store to your Applications folder.
- Run Disk Maker DMG installer and copy the app to the Applications.
- The application will automatically detect the downloaded macOS as shown in the screenshot. Select 'Use this Copy' if you would like to proceed with it.
- Next is setting the USB pen drive for creating the bootable installer. Choose the third option ' An 8 GB USB Thumb drive.'
- The app will list all drives in your system. Pick the one you would like use as macOS USB installer.
- Ignore the warning message and proceed to Erase and Create macOS USB disk. Don't forget to provide your admin password when it prompts.
- Keep checking notifications tab for progress. When it completes you will find Install macOS Mojave (or High Sierra) mounted to your desktop as a USB disk.
- That's your backup. Unmount and keep the USB installer to a safe place.
Does paint tool sai work on mac. What is the alternative if I don't have usable Mac at the moment?
This method is applicable when you have a Mac, and the internet recovery fails. But think about a situation when your only Mac stops to boot, and you don't have USB installer or TimeMachine backup! Downloading Mac OS DMG file might save you. If you have a macOS DMG, you can create bootable USB disk from a Windows PC — use a software like TransMac for this purpose.
Clean installing or restoring a Mac offline with USB pen drive
As said earlier, you could use the macOS USB installer to do a clean install or restore it upon a boot failure. Just connect the USB disk and press the Option/Alt Key when you hear the boot sound. The Mac will then display all the startup disks available.
Pick the USB drive with the label 'Install macOS Mojave or High Sierra' and follow on-screen instructions to complete the installation. If you need, use the Disk Utility to format the drive for doing a clean install.
