in context: Microsoft introduced the original version of the Refs in 2012 with the Enterprise-Centenary Windows Server 2012. At that time, the company said that the new file system was intended to replace NTFs. However, NTFs remain the real standard for storage and file management in modern Windows versions.
Finally, Microsoft is action with its flexible file system (RFS) technology. Despite being 14 years old, storage format is largely unfamiliar to most Windows users. However, it is now being recently offered as an alternative option in Windows 11 Preview Build.
Discovered by a vendor Windows Insider, the new option appears in Windows 11 Build 27823. According to him, a hidden menu – has been accessed through an invisible button – allows users to formulate partitions and involuntary disks using a new “flexible storage” option. A pop-up menu then provides two file system options: default NTFS format or RFS technology.
I could not find any particular relevant information about the “flexible storage” monin on Google, so it is not clear what Microsoft means by the word. Meanwhile, Redmund offers a basic observation of refs on its microsoft learn network. The new file system is designed to support large storage capabilities, improve efficiency in scales large datasets and provide maximum flexibility against data corruption.
The Windows file is designed as the “next generation” of the system and a potential replacement for NTFS, the referee provides significant improvement on aging storage technology, which returns to Windows NT 3.1. A refs partition can be formatted up to 35 petabytes and even the same file can be large in full quantity. In contrast, NTFS volume is maximum at 256 terabytes.
For this, the button is in a very normal place. pic.twitter.com/cftyjzwnfv
– Phantomofearth 🌳 (@Phantomofearth) March 26, 2025
The refs introduces advanced features such as block cloning, file-level snapshot, and more. However, it lacks traditional NTFS capabilities (see a comparison table here), which includes bootable volume, file compression, encryption, short file name and support for removable media. Microsoft states that these characteristics are “unavailable at this time,” suggesting that they can be added in the future… or perhaps not.
Despite being a highly advanced storage technique, the refs remains an enterprise and a server-centric solution for now. The hidden menu discovered in Windows 11 Build 27823 may indicate Microsoft’s intentions to bring referee to Windows’s consumer versions.
Meanwhile, the Open-SOS community is working on informal refs documentation, and the German company Paragon Software offers its own closed-source Refs Driver.
