Windows 11 Still Has Internal Version 10.0 — Same as Windows 10

Windows 11 has been released for nearly five years, but internally the system is still identified as «10.0». Anyone can verify this: run systeminfo in Command Prompt and see «Microsoft Windows 11» in the product name line and «10.0» plus the build number in the OS version line. For example, for 25H2 it looks like 10.0.26200.

It's not a bug or a leftover update

The same principle is enshrined in Microsoft documentation: in the Windows versions table, Windows 7 is marked as 6.1, Windows 8 as 6.2, Windows 8.1 as 6.3, Windows 10 as 10.0, and Windows 11 appears in the next row with the same number 10.0. That is, the marketing name and internal NT kernel version have never aligned: Windows 7 was not NT 7.0, and Windows 8.1 was not NT 8.1. Simply Windows 10 happened to coincide with NT 10.0, and for several years there was a misleading impression that the numbering had become logical.

Why Microsoft doesn't change this number

The main suspicion is compatibility with legacy software. Programs have for decades checked the OS version and often do so incorrectly. Windows veteran Raymond Chen described a classic case: «The GetVersion function in Windows 95 reported version 3.95 instead of the expected 4.0 because too many programs performed incorrect version checks». The reason was that applications compared major and minor version numbers separately, so the condition «Windows 3.1 or newer» broke at zero in «4.0».

Later Microsoft went even further: starting with Windows 8.1, APIs like GetVersionEx return a version depending on which Windows releases are declared in the application manifest. An application without the appropriate declarations can still receive 6.2 in response — the Windows 8 number. Developers are instead offered helpers like IsWindows10OrGreater and «greater than or equal to» comparisons that don't break with new releases. Microsoft has not published an official explanation that compatibility is the reason for retaining NT 10.0 for Windows 11 — this remains an assumption.

What actually distinguishes releases

The practical conclusion is simple: the 10.0 prefix today carries no useful information. Modern builds should be distinguished by build number: Windows 11 24H2 is 26100, 25H2 is 26200, and 26H1, intended primarily for new devices rather than updating existing PCs, is 28000. The same logic can be seen in developer tools: Windows SDK versions still have the form 10.0.26100.x or 10.0.28000.x. So «Windows 11 25H2, version 10.0, build 26200» represents three correct descriptions of the same system at different numbering levels.

The temptation to conclude from this «Windows 11 is just Windows 10 with rounded corners» is false: they have different hardware requirements, different basic security requirements, modified shell components, new APIs, and a different servicing model. The common major version number is rather an archaeological detail than a technical assessment. Whether Microsoft plans to ever synchronize the internal version with the product name remains to be clarified.