If you've recently downloaded a Windows ISO or used the Media Creation Tool, you may have noticed something that feels a little off. The download seems bigger than it used to be. Perhaps you dismissed it as a lingering memory of older, slimmer installers. But according to recent data, your instincts are correct: Windows installation files have been quietly ballooning in size, and artificial intelligence is largely to blame.
Microsoft's ISO downloads for Windows have now crossed the 8GB threshold, marking a dramatic doubling in size over the last decade. The trend is especially visible in the Windows 11 lifecycle, where the cumulative updates and installation files have swelled at a pace that even seasoned deployment experts say is striking. To understand what's happening, we need to look at how Windows installers have evolved, what the AI connection is, and why this matters more than just a few extra gigabytes on your hard drive.
The growth of Windows installer files
For years, Windows installation media followed a predictable pattern. Each successive version of Windows would grow modestly, but the pace was generally manageable. That changed noticeably with Windows 10, and the trend has accelerated sharply with Windows 11. A recent analysis by a prominent Windows deployment expert, Michael Niehaus, shows just how dramatic the growth has become. Using data from Microsoft's Visual Studio subscriptions, Niehaus charted the increase in size for multi-edition ISO downloads, starting with the initial release of Windows 11 version 24H2 in November 2024 through the latest version 25H2 from July 2026. Even though 25H2 was delivered as an enablement package for 24H2, the installation files have grown substantially in a relatively short period.
According to Niehaus, almost 6,000 new folders and over 20,000 new files were added to the Windows 11 installation media in less than two years. That's not just a routine update adjusting a few drivers or system files. It's a massive expansion of the Windows codebase, and it has a direct impact on download times, storage requirements, and the complexity of IT deployments.
To put this into historical perspective, I went through my own collection of ISOs to plot the change in download size since the initial release of Windows 10 in 2015. The original Windows 10 ISO was approximately 4GB. The latest Windows 11 ISO is well over 8GB, and even the Media Creation Tool, which uses a more optimized download process, delivers a file that is 6.8GB. That's nearly twice the size of the original Windows 10 release. It's no wonder that users with fast internet connections but relatively small storage drives are starting to run into trouble.
What is causing the bloat?
The question on everyone's mind is: why has Windows gotten so much larger? The answer lies in Microsoft's aggressive push into artificial intelligence, particularly the features designed for Copilot+ PCs. Copilot+ is Microsoft's umbrella term for AI-powered experiences integrated directly into Windows, such as live captions, image generation, and the Windows Copilot assistant that helps users with tasks across the operating system.
Many of these AI features rely on local AI models running directly on the device, rather than in the cloud. That's a key selling point for privacy and responsiveness, but it also comes at a cost. These AI models are large files, and they are being bundled with Windows updates and installation media. Niehaus estimates that approximately 3GB of shared AI models are now included in the cumulative updates for Windows 11. These files are necessary for Copilot+ PCs, which have dedicated neural processing units (NPUs) to run the models efficiently. However, Microsoft ships these files to all Windows 11 devices, including those without an NPU. On a traditional PC, the installer downloads these AI components and then ignores them, but they still occupy space in the installation media and consume bandwidth during download.
As Niehaus puts it, “Is Windows getting bigger? Yes. Are updates getting bigger? Yes. Does Copilot+ make it worse? Yes, much worse.” This is a frank assessment from someone who spent 16 years at Microsoft working on Windows deployment. His insight is valuable because it confirms that the growth is not just a perception problem or a side effect of regular feature updates. It's directly tied to Microsoft's AI strategy.
The storage dilemma
The growing size of Windows installation files is not just a theoretical concern. It has real-world consequences for anyone who owns a PC with a modest storage drive. Microsoft's official system requirements for Windows 11 state that a minimum of 64GB of storage is needed for the system drive. That may have sounded generous a few years ago, but it is now dangerously tight. I ran a test in a virtual machine with a 64GB virtual drive and installed the latest Windows 11 release, including all pending updates. The peak storage usage reached 28.2GB before the operating system was fully installed. That means the system drive was nearly half full after installing Windows and its updates, leaving very little room for applications, user files, or even the temporary files that Windows creates during normal operation.
This situation is reminiscent of earlier eras of Windows bloat. Back in the days of Windows XP, reviewers complained about the operating system requiring two gigabytes of hard disk space—at the time, that seemed enormous. Today, we're looking at a 64GB drive being filled to the brim by the operating system alone. The difference is that hardware prices are currently high, and the cost of adding more storage has increased significantly. The "just add more hardware" approach that used to work is becoming less feasible for many consumers and businesses.
Deployment expert Niehaus suggests that 128GB should now be considered the bare minimum for a Windows 11 system drive. For anyone doing serious development, creative work, or running virtual machines, a terabyte or more is recommended. That's a significant shift from the official Microsoft requirements, and it's driven largely by the AI-related files being packed into modern Windows releases.
Why does this matter for IT professionals?
For enterprise IT administrators, the growing size of Windows installation files complicates the task of deploying and updating Windows on corporate networks. Every time Microsoft releases a monthly cumulative update, the update package is now several gigabytes larger than it used to be. That means more bandwidth is consumed on the corporate network, more time is required for the updates to download and install, and more disk space is needed on client devices. For organizations that manage thousands of PCs, these factors can add up to significant operational overhead.
There is also the question of how Microsoft distributes these AI components. Currently, many of the AI models are shipped as part of the monthly cumulative updates that go out to every Windows 11 device. This approach ensures that all devices receive the components, but it also means that devices that cannot use them—because they lack the necessary NPU hardware—still have to download the files. Microsoft has the ability to distribute system components through the Microsoft Store instead, which would allow the company to deliver AI features only to devices that actually support them. The Store-based delivery has the added advantage that it does not require a system restart, making it less disruptive to users.
In fact, Windows 11 already uses the Microsoft Store for some critical components. When you go to the Downloads & Updates page in the Store, you can see a list of system components that are now managed through the Store rather than Windows Update. These components download only when needed and do not require a reboot. Extending this approach to AI models would reduce the burden on Windows Update and avoid wasting bandwidth on upgradable hardware.
Of course, the decision to ship AI bits through the standard update channel may be a deliberate one. Microsoft likely wants to ensure that Copilot+ features are available as quickly as possible when users buy new hardware. But the trade-off is that these large files are now clogging every Windows installation media and update package, regardless of whether they are actually used.
What does the future look like?
The trend toward larger Windows downloads shows no signs of reversing. As AI becomes more deeply integrated into the operating system, we can expect to see even more local models and related files added in future versions. This is not inherently a bad thing—local AI processing is much faster and more private than relying on cloud services. But it does require Microsoft to be more thoughtful about how it delivers these components. It also requires users and IT departments to plan for the growing storage footprint of Windows.
If you're an individual user with a PC that has a 64GB system drive, it may be time to consider upgrading to a larger SSD or to clean up your existing storage to make room for the inevitable updates. If you're responsible for deploying Windows in a business environment, you should revisit your hardware requirements and think carefully about whether the minimum specifications on paper are sufficient for the reality of today's Windows update cycle. And if you're concerned about the bandwidth costs of distributing multi-gigabyte updates across a large number of machines, you may need to explore tools like Windows Update for Business, delivery optimization, or third-party endpoint management solutions that can help reduce the impact.
The revelation that AI is driving the growth of Windows downloads is a reminder that every new feature comes with a cost. Copilot+ PCs promise genuinely useful capabilities, but those capabilities have to be delivered somehow. The question is whether Microsoft will find a more efficient way to deliver them in the future, or whether we will simply accept that Windows installers are destined to get bigger with every release.
Source: ZDNET News