Your Windows download keeps getting bigger, and AI is to blame - here's why it matters

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Windows downloads are bigger than ever. I noticed this a few times over the past six months ("Huh, I don't remember a download being this big before") but hadn't had time to dig into the details.

Then I saw a recent post from Michael Niehaus titled "How can Windows 11 keep getting bigger?" and I realized, no, it was not my imagination.

Also: Microsoft goes all in on new AI-powered Windows security strategy - what it means for you

Here's Michael's chart showing the increase in size for multi-edition downloads from Microsoft's Visual Studio (subscription required). The first value is from the initial release of Windows 11 version 24H2 in November 2024 up through the latest, version 25H2 from July 2026. (Because 25H2 was delivered as an enablement package for 24H2, both releases are from the same branch.)

Windows deployment expert Michael Niehaus has been charting the growth of Windows installer ISOs

As Michael notes, almost 6,000 new folders and over 20,000 new files were added over that stretch of less than two years.

I went through some additional ISO from my collection to plot the change in download size since the initial release of Windows 10 in 2015. See for yourself.