This step creates the structure for the installer. In recent versions of macOS, the createinstallmedia tool might download the actual payload during the creation process if it isn't found locally. Ensure you have a stable internet connection while running this command to ensure the installer is "complete" and ready for offline use.
softwareupdate --fetch-full-installer --full-installer-version 11.7.10 Use code with caution. Copied to clipboard macos big sur download offline installer
(Replace 11.7.10 with the latest available build of Big Sur). This command forces macOS to download the full Install macOS Big Sur.app into your Applications folder. From there, you can copy it to a USB drive or use it to create bootable media. This step creates the structure for the installer