Windows 10 in May recorded its largest increase in user share since August 2015, the first full month after its launch last summer, data published Wednesday showed.
The impressive increase came after Microsoft began what will likely be its last big push to put the free Windows 10 on customers' PCs, a campaign that started mid-May and featured a much-derided trick to get users to approve the upgrade from Windows 7 and Windows 8.1.
According to U.S.-based analytics vendor Net Applications, Windows 10 powered 19.4% of all Windows PCs in May, a 2.1-point increase from the month before. Net Applications measures user share -- an estimate of the percentage of the global PC population that runs a particular operating system -- by tallying unique visitors to clients' websites.
The 2.1-point rise in user share was the second largest one-month gain for Windows 10, bested only by August 2015's whopping 5.3 percentage points. Microsoft released Windows 10 on July 29 of last year.
With the big boost in user share, Windows 10 will easily surpass the 20% mark by the end of June, as Computerworld forecast four weeks ago. If the growth trend over the last 12 months holds up, Windows 10 will reach the 22% milestone -- 22% of all Windows PCs -- by the end of July, just days after Microsoft issues its next major upgrade for the operating system, which it has tagged "Anniversary Update."
Assuming Windows 10 makes reaches 22% of all Windows personal computers in its first year, it will have beaten the adoption record of 2009's Windows 7, which collected a 20% share in its first 12 months.
Windows 10 now powers approximately 292 million systems, according to Computerworld's calculations, which used Net Applications' numbers and Microsoft's oft-cited claim that 1.5 billion machines run Windows. That represented an increase of about 33 million in May, or just over 1 million each day. By comparison, nearly 4 million Windows PCs were upgraded to Windows 10 each day during the first complete week of its availability, Aug. 2-8, 2015.
In early May, Microsoft claimed that 300 million "active devices" were then running Windows 10. Unlike Net Applications, which tallied only personal computers, the Redmond, Wash., company also counted tablets, smartphones, the Xbox One video game console and other devices that run Windows 10 or a variant.
Other sources confirmed Windows 10 growth during May.
Irish vendor StatCounter pegged Windows 10's global usage share -- a different metric than Net Applications' that reflects online activity -- at 20% for May, an increase of 2.1 percentage points from the month prior and the largest gain since September 2015. Meanwhile, the Digital Analytics Program (DAP) tapped Windows 10 at 25.3% of all Windows PCs, an increase of 1.5 percentage points over April.
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