To get the smallest official Windows 11 installation file, you should use the Media Creation Tool, which creates an ISO using higher-compression .esd (Electronic Software Download) files rather than the standard .wim format found in direct downloads. Official Download Options
Best Practices for Downloading Windows 11
Step 4: Delete the original install.wim and replace it with your new install.esd.
Final Recommendations
3. User reports (forums, Reddit, etc.)
Searching for a "highly compressed" Windows 11 ISO often leads to unofficial sources that claim to offer the operating system in a much smaller file size (e.g., 2GB or less) compared to the standard 5GB+ official image. While these "hot" downloads are popular for users with limited data or older hardware, they come with significant security and stability risks. The Truth About "Highly Compressed" ISOs
UUP Dump (uupdump.net) aggregates Unified Update Platform files. You can generate a custom script to download and compile an ISO that is already in highly compressed ESD format.
.exe, .zip, or .iso file.