Windows 11 squeezed to 699,811,840 bytes fits on CD

A Windows 11 ISO image has been compressed to 699,811,840 bytes, small enough to fit on a standard 700 megabyte compact disc.

The work was carried out by a developer using a tool called Pico11, who published an image file that measures exactly 699,811,840 bytes and still provides an active desktop and a set of basic Microsoft utilities. The project author uses the alias NTDEV.

NTDEV described the project as a proof of concept. "This is a proof of concept I cobbled together to see how far the Windows 11 ISO could be shrunk while keeping an active desktop and a few familiar apps," the developer said. The compressed build omits a large portion of system files but continues to run applications such as Calculator, Notepad, Paint and the Settings app.

The teardown also replaces the native Task Manager with an interface resembling older Windows versions, apparently to save additional space. NTDEV emphasized that the image is experimental: it removes servicing and update functionality and is not intended to replace a daily driver installation of Windows.

Availability and tool lineage

Pico11’s capabilities are set to be published on GitHub under the Tiny11 name. The developer notes that earlier iterations of these tools enabled an experimental Windows run with as little as 176 megabytes of RAM, and have also produced more practical custom builds around two gigabytes in size.

The immediate release plan is a GitHub publication of Tiny11, which will expose Pico11’s methods and allow others to reproduce or adapt the compression approach.