Windows Vista saw a smaller 4.62 percent of traffic that same month.
The OS' positions were switched in May when the W8 numbers sat at 4.27 percent, edged out by Vista's 4.51 percent of web traffic.
Interestingly, both operating systems gained market share between the months of May and June.
Windows 7, XP still on top
Predecessor Windows 7 took home the crown in June with 44.37 percent of web traffic, and age-old Windows XP proved its resilience with 37.17 percent.
Combined, Net Applications' numbers show a steady 91.51 market share for all Windows operating systems.
Compared to other operating systems
Windows 8 is making small strides, leaving behind other, less popular operating systems.
Lumped into an "Other" category at 2.11 percent are Linux and older Windows and Apple platforms like Windows 98 and Mac OS X 10.5 and below.
Behind them are more recent Apple operating systems, Mac OS X 10.6 at 1.76 percent, OS X 10.7 at 1.73 percent and the most recent OS X 10.8 completing the pie at Pie, 3.14 percent.
To be fair, since Apple's operating system is refreshed yearly, Mac OS X stood its ground at a more respectable 7.2 combined market share.
- Read about the 12 key changes coming to Windows 8.1
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