Back in July, Microsoft tempered its Windows 10 expectations a touch, noting that its initial projection of mid-2018 for one billion active devices was probably a bit over-ambitious. That pronouncement came shortly after the company announced that its OS had hit 350 million machines (after hitting 300 million in May) — and roughly a fortnight before ending its free upgrade period.

Three months after that last major update, Microsoft’s got another big round number to celebrate during the kickoff to the Microsoft Ignite event in Atlanta, noting that Windows 10 has now hit 400 active million machines.

That list includes a wide range of devices, including the standard PCs, phones and tablets, along with the Xbox One, Surface Hubs and HoloLens. As far as what “active” means, the company is referring to machines that have been used at some point in the last 28 days.

The number has, notably, slowed in recent months, owing in part to the aforementioned end of the free upgrade period, which officially came to a close on July 29. Microsoft still anticipates that the operating system will eventually hit one billion devices, but at the moment, at least, it doesn’t have a specific deadline for that massive number.