Windows 11 reaches one billion users 150 days earlier than Windows 10

Microsoft has, according to its statements, surpassed one billion users for Windows 11. The current operating system reached this milestone within 1576 days of its introduction. This means Windows 11 cracked the billion mark exactly 150 days faster than its predecessor, as Windows 10 took 1706 days to reach one billion. However, it is unclear so far whether the billion refers to daily active users, what proportion new devices make up, and how many performed the update from Windows 10.

Microsoft CEO Satya Nadella omitted these details when he mentioned the billion mark during a conversation with analysts on the occasion of the latest quarterly figures. Recently, Microsoft exceeded expectations, but the stock market punished the weaker cloud outlook. “Windows has reached a major milestone: 1 billion Windows 11 users,” Nadella said. “An increase of over 45 percent compared to the previous year.”

Windows 10 slower to the billion

Windows 11 likely saw another increase in user numbers in December. During the in-house trade fair Microsoft Ignite in mid-November 2025, Windows chief Pavan Davuluri explained that “almost a billion people rely on Windows 11.” This mark has apparently been reached since then. The predecessor operating system reached the billion mark almost exactly six years ago. In mid-March 2020, Microsoft announced that Windows 10 was running on one billion devices.

Microsoft had actually intended to achieve this two years earlier. But already in mid-2016, the company had to admit that 1 billion Windows 10 installations by 2018 were not achievable. Microsoft justified this by focusing on the smartphone hardware business. However, this was short-lived, as about a year later, in the fall of 2017, Microsoft sidelined Windows Mobile.

Sluggish Windows 11 migration

Windows 10 is now also found there, as Microsoft has since discontinued support for this operating system, meaning users no longer receive updates. Since this also affects security updates, any security vulnerabilities remain open. These could be exploited by cybercriminals to expand their rights in systems, establish a foothold, or move within networks for espionage or ransomware attacks, for example. For such systems, Microsoft offers extended support for Windows 10, including for private users.

Nevertheless, Microsoft has not been able to establish Windows 11 so far, as user numbers for Windows 10 have even increased again, according to statistics from last fall. For December 2025 as well, market researchers at Statcounter report increased user numbers for Windows 10, while they have decreased for Windows 11. In January, however, the trend reversed again, so that Windows 11 now accounts for 62 percent market share of all Windows systems, while Windows 10 drops to 36 percent.

(fds)