Depending on your current system, use one of the following official channels:
Apple provides "Combo" and standard updates for specific versions: mac os x 1013 high sierra dmg download hot
You can find the macOS High Sierra page in the App Store. Note that searching for it directly may not work if your Mac is running a newer OS; you must use a direct link to trigger the "Get" button. Depending on your current system, use one of
Third-party tools like Mist or the macadmin-scripts on GitHub can help automate the download and conversion to a DMG file. Compatibility & Safety Compatibility & Safety macOS High Sierra 10
macOS High Sierra 10.13.6 Combo Update (recommended for updating from any version of 10.13). macOS High Sierra 10.13.6 Update .
The standard App Store download provides an .app file in your Applications folder, not a .dmg . To create a bootable disk image or USB drive for a clean installation: