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ChromeOS Flex and macOS Dual Boot on Intel Mac

Guide 10-33989 · Updated · Step by step

Yes, you can dual boot ChromeOS Flex and macOS on an Intel Mac, but with important caveats. ChromeOS Flex is designed to replace an existing operating system, not to coexist with it through Apple’s Boot Camp utility, which officially supports only Windows. However, you can achieve a dual-boot setup by installing ChromeOS Flex to a separate internal partition or an external USB drive and using a third-party boot manager like rEFInd to choose between macOS and ChromeOS Flex at startup.

Why Dual Booting Is Not Straightforward

ChromeOS Flex is Google’s official operating system designed to breathe new life into older PCs and Macs. It is based on Chromium OS and is intended to be installed as the sole operating system on a device. Unlike Windows, which Apple explicitly supports through Boot Camp, ChromeOS Flex does not have an official dual-boot installer. The ChromeOS Flex installer will happily overwrite your entire disk, so you must manually partition your drive and use a custom bootloader to make dual booting work.

What You Need Before You Start

  • An Intel-based Mac from 2012 or later (check Google’s certified models list for compatibility).
  • A USB drive with at least 8 GB of storage for the ChromeOS Flex installer.
  • A second USB drive or a free partition on your internal drive (at least 16 GB, but 32 GB or more is recommended).
  • Time and patience—the process involves several command-line steps and a third-party boot manager.

How to Dual Boot: Step-by-Step Overview

  1. Back up your Mac. Partitioning and installing a new OS carries a risk of data loss. Use Time Machine or another backup method.
  2. Create a ChromeOS Flex installer. Use the Chromebook Recovery Utility extension in Chrome on any computer to write the ChromeOS Flex image to a USB drive.
  3. Partition your internal drive. Use Disk Utility (in macOS Recovery) to shrink your macOS partition and create a new partition (MS-DOS (FAT) or exFAT) for ChromeOS Flex. Note the disk identifier (e.g., disk0s4).
  4. Boot from the ChromeOS Flex installer. Restart your Mac while holding the Option key, select the USB drive, and follow the installation prompts. When asked where to install, choose the partition you created.
  5. Install rEFInd. After ChromeOS Flex is installed, boot back into macOS, download rEFInd, and run its install script from Terminal. This replaces Apple’s boot picker with a graphical menu that lists both macOS and ChromeOS Flex.
  6. Reboot and select your OS. Each time you start your Mac, rEFInd will appear, letting you choose between macOS and ChromeOS Flex.

Common Problems and How to Fix Them

  • ChromeOS Flex doesn’t see the partition. Ensure the partition is formatted as MS-DOS (FAT) or exFAT; ChromeOS Flex may not recognize APFS or HFS+ partitions.
  • rEFInd doesn’t show both OSes. Run sudo rEFInd-install again, or manually edit the refind.conf file to add a scan for the ChromeOS partition.
  • Wi-Fi or graphics don’t work in ChromeOS Flex. Check Google’s certified models list. Some older Macs may have unsupported Wi-Fi chips; a USB Wi-Fi dongle can help.
  • macOS won’t boot after installing rEFInd. Boot into macOS Recovery (hold Command+R at startup) and reinstall macOS; this will replace the bootloader but keep your data intact.

Alternative: Install ChromeOS Flex on an External Drive

If you don’t want to modify your internal drive, you can install ChromeOS Flex on a fast external USB drive or Thunderbolt SSD. This is simpler and safer: you boot from the external drive when you want ChromeOS Flex, and your Mac boots normally to macOS when the drive is unplugged. The main downside is performance—USB 3.0 drives are slower than internal SSDs, and you need to carry the drive with you.

Should You Do It?

Dual booting ChromeOS Flex and macOS on an Intel Mac is possible but not officially supported, and it requires comfort with command-line tools and partitioning. If you just want to try ChromeOS Flex, consider running it in a virtual machine (like VirtualBox or UTM) first—this is far less risky and doesn’t touch your internal drive. If you have an older Mac that no longer receives macOS updates, ChromeOS Flex can give it a new lease on life, but you might be better off replacing macOS entirely with ChromeOS Flex, which is what Google intends.

Frequently Asked Questions

Will dual booting void my Mac’s warranty?

No, but it can make troubleshooting more complex. Apple will still service the hardware, but they may not provide software support for a custom bootloader or ChromeOS Flex.

Can I use Boot Camp to install ChromeOS Flex?

No. Boot Camp Assistant only supports Windows. You must use the manual partition method described above.

Will ChromeOS Flex run well on my 2015 MacBook Pro?

Generally yes, if the model is on Google’s certified list. ChromeOS Flex is lightweight and performs well on older hardware, but some features like the Play Store (Android apps) are not available on all devices.

Can I switch back to macOS only if I change my mind?

Yes. You can remove the ChromeOS Flex partition and reinstall rEFInd, or simply erase the partition in Disk Utility. Your macOS data remains intact as long as you don’t delete the macOS partition.

Is there a risk of losing data?

Yes, any time you partition or install an OS, there is a risk. Always back up your Mac completely before starting.

Related

General steps for current mainstream versions; menus can differ by device and version. See the disclaimer or report an error.

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