Step 1: Download the Official macOS Big Sur Installer (2021)
Many online forums, tech blogs, and torrent sites offer direct download links for pre-made macOS Big Sur ISO files from 2021. While convenient, downloading pre-compiled ISO files from unverified third-party sources poses significant security risks:
Apple does not officially distribute macOS as ISO files. They distribute .app installers. This guide shows you how to legally download the installer and convert it to a bootable ISO for use in virtual machines (VMware, VirtualBox, UTM) or legacy installers. macos big sur iso 2021
Launch the Terminal application, which can be found in the Utilities folder within your Applications folder.
35.5GB available for upgrades; up to 44.5GB for earlier releases. Step 1: Download the Official macOS Big Sur
mv ~/Desktop/BigSur.cdr ~/Desktop/BigSur.iso
For the safest experience, use the VMware Unlocker and follow the step-by-step installation guides. macOS Big Sur marked a transformative era for Apple, and with these tools, you can still experience it today in a safe, virtualized environment. This guide shows you how to legally download
Use createinstallmedia , then convert the file from .dmg to .cdr using hdiutil , finally renaming it to .iso . Requirements & Resources