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—and they don’t—then there would be 1.65 billion Windows users worldwide. That is the minimum size of this user base.

But the user base is almost certainly bigger than that. In fact, it could be much bigger.

Let’s say 50 percent of Windows 7/8.x users do not send in telemetry data. In this scenario, there would be 3.3 billion Windows users worldwide. That seems quite high to me. But this, perhaps, the upper bound of the possible user base size.

The average of these two figures, incidentally, is about 2.48 billion. Is this roughly accurate?

To get closer to the truth, we have other sources of data to consider. NetMarketShare, for example, measures pure usage share—actual PCs out in the world accessing the web—so their data isn’t reliant on telemetry. How does Microsoft’s data jibe with that from NetMarketShare (which we know Microsoft trusts)?

Looking at its current desktop OS usage share data, it appears that Windows 10 represents only 29 percent of all PCs in use. That data includes Macs and Linux, however, and if you filter those out, you get about 25 percent.

That’s roughly half the percentage that Microsoft is reporting (48 percent). And while we can excuse that difference in various ways, the most obvious, I think, is that the NetMarketShare data may show us roughly how many Windows 7/8.x PCs there are in the world that are not sending telemetry data back to Microsoft.

Is it possible to use that assumption to do some math to arrive at a rough figure for the real Windows user base?

No. But if we assume that both numbers are accurate, then there are 2.2 billion Windows PCs in the world: 550 million is 25 percent of that 2.2 billion.

(We could then use that to determine how many (and what percentage of) Windows 7/8.x PCs are/are not sending telemetry data to Microsoft. I’m a bit less worried about that. Plus, this is all very squishy.)

Is 2.2 billion accurate? Maybe. There could be all kinds of errors in my math, of course. And my assumptions could be wrong.

In any event, it is a big number. And big numbers are usually good when it comes to software platforms: They create a virtuous cycle by which developers are attracted to the platform and users become more engaged because the platform is so well-supported.

But this traditional view doesn’t appear to apply to Windows anymore. Developer and user excitement is on mobile and the web, both of which are even bigger platforms. And engagement on both is much higher, too. This all helps to explain why Microsoft tried to jam a mobile apps platform into Windows. And why, when that failed, it started pinning its hopes, in part, on the web with Progressive Web Apps.

Will we ever know the truth of the Windows user base? I doubt it.