How Many Windows Users? (Premium)

Recent data suggests that the overall Windows user base may be bigger than I previously thought. To find out why, we'll need to do some math. And as with all math of this nature, it will require some educated guesswork. Microsoft will never give us all the data we need to arrive at a true figure.

So. In an announcement about some new Windows 10 store trends, Microsoft notes that "Windows 10 is now on more than 600 million monthly active devices, ranging from Xbox One consoles, tablets, laptops, Windows Mixed Reality headsets and more." We already knew about the 600 million figure; it dates back from late November and is probably still accurate given that most on-boarding Windows 10 users are upgrading and not new users.

As important, my belief is that this number equates very closely to actual users. Compared to the way that Microsoft used to measure the success of Windows---via licenses sold, which did not indicate real-world usage---the 600 million figure is what I think of as a hard number.

But that number doesn't accurately measure the size of the Windows 10 user base on PCs. Some of the devices in that count---Xbox Ones, especially---are not PCs. So what's the real number for Windows 10 PCs?

To figure that out, we must first find out how many of those other devices are out there in the world.

The Xbox One represents the biggest non-PC chunk. And we know that the Xbox One installed base is about 35 million units. So that one is easy enough.

Windows phone, curiously, doesn't factor into this much at all. And that's true even though it's not clear whether Microsoft is counting Windows phones in that 600 million figure. I believe that it is. But, again, it doesn't matter.

Why? Because math.

There were 2.3 billion to 2.4 billion smartphone users worldwide in 2017, depending on which source you trust. Of that total, 0.15 percent were Windows phones, according to NetMarketShare. So the number of Windows phones still in use around the world is about 3.6 million. How many of those are on Windows 10? That is harder to say with certainty, but the latest data I could find, from AdDuplex, suggests that about 20 percent of Windows phone in use are/were running Windows 10. That's less than one million units/users, which is negligible.

So, at most, there are about 50 million non-PCs in that Windows 10 figure. So I'm going to go with 550 million Windows 10 PCs and/or users.

According to Microsoft's newly-updated Windows and Microsoft Store trends page, Windows 10 today accounts for 48 percent of all Windows usage, with the one caveat that this data is "obtained from customers who have opted to send [Microsoft] telemetry data." My belief is that many (if not most) of them do so. For Windows 10, that is certainly true, since doing so is essentially compulsory.

This one requires a real guess, however. How many Windows 7 or 8.x users are not sending in telemetry data?

If all Windows users send telemetry data...