Micro soft this week bumped up its claim of Windows 10 devices to 75 million when a company executive tweeted that figure.

"More than 75 million devices running Windows 10 -- and growing every day," Yusuf Mehdi, corporate vice president of Micro soft's Windows and Devices division, said on Twitter. 

Mehdi had last updated the official Windows 10 tally on July 30, when he said 14 million devices were running the new OS. Micro soft began triggering on-screen Windows 10 upgrade notifications on PCs running Windows 7 and 8.1 on July 29.

While the 75 million cannot be independently verified -- Microsoft is likely citing the number of Windows 10 "activations," the check-in the OS does with Redmond's servers when it's first run to verify that it is linked with a valid product key -- it is in the ballpark of third-party estimates.

Data provided to Computerworld earlier this month by analytics vendor Net Applications showed that by its calculations 3% of all Windows-powered personal computers ran Windows 10 during the week of Aug. 2-8. That 3% translated into approximately 45 million devices, assuming there are 1.5 billion Windows systems worldwide, the latter number one that Micro soft itself has repeatedly used.

It's not unreasonable to think that Micro soft has added another 30 million copies of Windows 10 to the running total in the three weeks since. (Net Applications has declined to provide more recent weekly user share data, saying that its engineers had disabled weekly reporting because they were revamping the back-end infrastructure to prep a new service.) 

Another analytics vendor, Dublin-based StatCounter, which tracks a different metric, has posted data that also appears to dovetails with Micro soft's 75-million device claim. The growth of StatCounter's usage share for Windows 10 -- a measurement of Internet activity -- since July 30 closely matches the increase Micro soft claimed.

The growth rate from 14 million to 75 million -- Mehdi's numbers -- represented a very strong 436%, give or take a decimal point.

Likewise, growth in StatCounter's Windows 10 usage share from the 1.34% on July 30 (when Mehdi touted 14 million near day's end) to the high water mark of 7.26% on Sunday, Aug. 23, was an almost-the-same 441%.

(Computerworld gave Windows 10 the benefit of the doubt, using the 7.26% of Aug. 23, rather than the lower usage share numbers during the work week just prior to Mehdi's announcement, because Mehdi was citing activations, or devices that could be running Windows 10 on any specific day. In other words, Computerworld assumed that 100% of the activated copies of Windows 10 were represented by the 7.26% usage share.)

Micro soft's 75 million was significantly larger than similar boasts in 2012 -- and earlier, compared to how fast previous Windows' editions left the gate. That's not a shock; everyone has expected a stronger uptake because Windows 10 is a free upgrade. Prior Windows editions were not.

In 2012, for example, Micro soft said it took Windows 8 a month to crack the 40-million-licenses-sold mark. In 2010, a little more than four months after Windows 7 debuted, the developer said 90 million licenses of that OS had been sold.

StatCounter's data supports the idea that Windows 10's start has been a record-setter for Micro soft. Windows 10's usage share after 30 days, for instance, was 37% higher than that of Windows 7 after its first 30 days of availability.

Micro soft has set a goal of putting Windows 10 on 1 billion devices within three years: The 75 million represents 7.5% of that target.

It's a good start.