WinBeta's inside sources are claiming that the Microsoft software has gained an additional 90 million users since October.
Such a leap sounds dubious but the figures take into account all devices, not just PCs, plus Christmas sales of Windows 10 hardware is sure to have helped its cause.
Microsoft is yet to reveal official install figures for Windows 10 since the 110 million downloads it announced in October.
However, the Redmond firm has started pushing its latest operating system even harder on Windows 7 and 8 users and employing some dubious tactics along the way.
The mobile version of the operating system recently launched with Microsoft's Lumia 950 handsets and is set to hit previous-generation Lumia devices over the coming months.