How to download Windows 10 21H1 ISO file (preview)

You can download the ISO file to perform an in-place upgrade or clean installation of Windows 10 21H1 ahead of the official release.

Windows 10 21H1 preview ISO download
Windows 10 21H1 preview ISO download

Although Windows 10 21H1 still in the development stage, Microsoft is now making available the ISO file as a preview, allowing Insiders to test the semi-annual update using a clean install or an in-place upgrade.

The ISO file is meant for commercial customers to test and validate the operating system before it becomes generally available. However, anyone can download it from the Windows Insider Preview Downloads page to start using the (nearly) final version of Windows 10.

The only caveat is you will be doing a full installation of the operating system with version 21H1 using the ISO file whether you choose to start with fresh installation or upgrade the current setup.

In this guide, you will learn the steps to download the ISO file to get early access to Windows 10 21H1. (You can also watch this video tutorial with the steps to get the ISO file.)

Important: The May 2021 Update is officially available, which means you can now download the ISO file directly from the main download page.

Download Windows 10 21H1 ISO file

  1. Open Windows Insider Preview Downloads page.

  2. Sign in with your Windows Insider Program credentials.

  3. Under the “Select edition” section, select the Windows 10 Insider Preview (Beta Channel) – Build 19043 option.

    Windows 10 21H1 ISO download
    Windows 10 21H1 ISO download
  4. Click the Confirm button.

  5. Select the product language.

  6. Click the Confirm button.

  7. Click the 64-bit Download button.

Once you complete the steps, the final ISO for Windows 10 version 21H1 will download on your device. If you are running the 32-bit version of Windows, you need to use the 32-bit Download button.

After downloading the ISO file, you can use tools, such as Rufus, to create a bootable media with a USB flash drive. If you plan to perform an in-place upgrade, you can simply double-click the file to mount the ISO with File Explorer and proceed with the setup process.

About the author

Mauro Huculak is a Windows How-To Expert who started Pureinfotech in 2010 as an independent online publication. He has also been a Windows Central contributor for nearly a decade. Mauro has over 14 years of experience writing comprehensive guides and creating professional videos about Windows and software, including Android and Linux. Before becoming a technology writer, he was an IT administrator for seven years. In total, Mauro has over 20 years of combined experience in technology. Throughout his career, he achieved different professional certifications from Microsoft (MSCA), Cisco (CCNP), VMware (VCP), and CompTIA (A+ and Network+), and he has been recognized as a Microsoft MVP for many years. You can follow him on X (Twitter), YouTube, LinkedIn and Email him at [email protected].