Macos Big Sur Iso 2021 ((free))

If you’re looking to run macOS Big Sur on a virtual machine like VMware or VirtualBox, or just want a bootable backup, you’ll need an ISO file. Since Apple only provides the

installer, you have to build the ISO yourself using the Terminal. ⚠️ Compatibility Check

Before starting, ensure your Mac is compatible. Big Sur supports MacBook 2015+ MacBook Air 2013+ MacBook Pro Late 2013+ . You will also need at least 15GB-20GB of free space Step 1: Download the Installer

You can download the official "Install macOS Big Sur" app directly from the Mac App Store . Once finished, the installer will sit in your /Applications folder. Do not run it yet! Step 2: Create the ISO via Terminal

and run the following commands, which involve creating a blank disk image, mounting it, and using the createinstallmedia tool to flash the installer files. hdiutil create -o /tmp/BigSur -size macos big sur iso 2021

g -layout SPUD -fs HFS+J -type SPARSE hdiutil attach /tmp/BigSur.sparseimage -noverify -mountpoint /Volumes/installBigSur sudo /Applications/Install\ macOS\ Big\ Sur.app/Contents/Resources/createinstallmedia --volume /Volumes/installBigSur --nointeraction Use code with caution. Copied to clipboard

Finally, finalize the ISO by detaching, converting the sparse image to a CDR format, and saving the final BigSur.iso to your desktop.

hdiutil detach /Volumes/Install\ macOS\ Big\ Sur/ hdiutil convert /tmp/BigSur.sparseimage -format UDTO -o /tmp/BigSur.iso mv /tmp/BigSur.iso.cdr ~/Desktop/BigSur.iso Use code with caution. Copied to clipboard You now have a BigSur.iso file on your desktop, ready for your virtual machine.

As of late 2023, macOS Big Sur is no longer receiving security updates. If this is for a primary machine, consider a newer macOS version. How to download macOS Big Sur If you’re looking to run macOS Big Sur

1. Background: Why Would Someone Want a Big Sur ISO?

Big Sur (macOS 11, released November 2020) was a major visual and architectural overhaul. By 2021, it was still being refined (11.2, 11.3, 11.4, etc.). Reasons people seek an ISO:

Running macOS on Windows/Linux hosts via VMware Workstation, VirtualBox, or Proxmox.
Creating a bootable installer without a Mac (e.g., using Rufus on Windows).
Legacy or experimental setups where a .app isn’t compatible with the hypervisor.

Part 4: Installing the 2021 ISO on VMware (Windows/Linux)

The 2021 ISO is specifically required for VMware because newer macOS versions (Ventura+) require hardware NVRAM fixes that break on older VMware versions.

Configuration for VMware Workstation Pro 17:

Create a VM: Guest OS: “Apple Mac OS X” -> “macOS 11.0”.
Hardware settings:
- CPU: 4 Cores (Enable “Virtualize Intel VT-x/EPT”)
- Memory: 8192 MB
- Hard Disk: SATA (Not NVMe) – 80GB minimum.
Unlocker: You must run the VMware Unlocker (macOS Unlocker for VMware) to reveal the Apple menu.
ISO Boot: Point the CD/DVD drive to your BigSur2021.iso.
The Hack: If the installer reboots, at the boot menu press F2 -> Virtualize CPU -> Enable “PMU Virtualization”.

The 2021 ISO will install in roughly 15 minutes. Do not accept updates to Monterey during setup. Running macOS on Windows/Linux hosts via VMware Workstation,

Part 1: Why “ISO” and Not “DMG” or “APP”?

First, a critical distinction. Apple does not officially release macOS as .iso files. Apple uses .app (installer application) bundles bundled inside a .dmg (Disk Image) or .pkg.

So why do people search for macOS Big Sur ISO 2021?

Virtualization: Software like VMware Workstation, VirtualBox, and Proxmox prefer .iso format for CD/DVD emulation.
Cross-Platform Flashing: Creating a USB installer on Windows or Linux requires an ISO, not a DMG.
Compatibility: Legacy bootloaders (Clover/OpenCore for Hackintosh) sometimes favor ISO structures.

Important: In 2021, macOS Big Sur version 11.6 (the final stable build of the "Big Sur" era before Monterey) is the specific version most users seek for stability.