The best places to find Windows ISOs
Installing and repairing Windows operating systems requires access to known, good, working, and virus-free installation, image, and supporting files. Typically, such collections can run into the tens or even hundreds of thousands of items, all organized within a complex hierarchy of file directories (folders, in Windows-speak).
That probably explains why the ISO format, originally developed to capture the contents of an entire optical disc (such as a CD, DVD, or even Blu-ray platter), makes a great container for something as big and complicated as Windows. When you go looking for a Windows download for installation or repair nowadays, it’s quite likely that what you’ll find is best described as either a “Windows 10 ISO” or a “Windows 11 ISO.” Readily available downloads now run from 4.6GB to over 6GB in size (4.557GB for Windows 10, and 6.345GB for 11, from Microsoft download pages in January 2024).