What’s taking up space on Windows 11? How to find out

The quick answer

1. Open Settings > System > Storage and look at the category bars.
2. Open Cleanup recommendations and clear what you don't need.
3. If System & reserved or Other is huge, check the hidden system files covered below.
4. If you still can't see where the space went, use a disk map to view every folder by size.

1. Storage settings

Go to Start > Settings > System > Storage. Windows scans the drive and shows bars for Installed apps, Temporary files, Documents, Pictures, System & reserved and others. Click Show more categories to see the full list. Click any category to open it.

The Other category is often the biggest surprise. It lists large folders Windows could not put in a category. Clicking one opens it in File Explorer, which is a good first lead.

If you have more than one drive, use Advanced storage settings > Storage used on other drives.

2. Cleanup recommendations

Microsoft's support article walks through this. In Settings > System > Storage, choose Cleanup recommendations. You get four groups:

• Temporary files, including old Windows Update files and the Recycle Bin.
• Large or unused files you have not opened in a while.
• Files synced to the cloud that can be made online-only.
• Unused apps.

Tick what you don't need and click Clean up in each section. Look closely at the Downloads folder entry under Temporary files. It is your real Downloads folder, not a cache.

Storage Sense, on the same page, can do some of this on a schedule, such as emptying the Recycle Bin and removing temporary files.

3. Disk Cleanup

The older Disk Cleanup tool still exists on Windows 11. Search for Disk Cleanup in the Start menu, pick the C: drive, then click Clean up system files. That second scan adds Windows Update Cleanup and, after an upgrade, Previous Windows installation(s). Those two are often the largest items in the list.

4. The hidden system files

These don't show up as normal folders in Storage settings, and File Explorer hides most of them. To see them in File Explorer, turn on View > Show > Hidden items. Don't delete any of them by hand. Use the built-in tools below.

WinSxS (the component store)

C:\Windows\WinSxS holds Windows components and older versions kept for rollback. File Explorer usually overstates its size, because many files in it are hard links that also appear elsewhere in Windows. Microsoft's documentation shows how to get the real number. In an administrator Command Prompt, run:

Dism.exe /Online /Cleanup-Image /AnalyzeComponentStore

The output lists the size Explorer reports, the actual size, and how much is Backups and Disabled Features plus Cache and Temporary Data. Those last two are the real overhead. If it says cleanup is recommended, run:

Dism.exe /Online /Cleanup-Image /StartComponentCleanup

Microsoft warns that deleting files from WinSxS yourself can stop Windows from booting or updating. Adding /ResetBase removes more, but then you can no longer uninstall the updates already installed. See Clean up the WinSxS folder.

hiberfil.sys

This file at the root of C: stores your memory when the PC hibernates. Its size is a percentage of your RAM, so on a machine with 32 GB of memory it can be many gigabytes. If you never use hibernate, you can turn it off from an administrator Command Prompt:

powercfg /hibernate off

That removes hiberfil.sys. It also turns off Fast Startup, which relies on hibernation, so cold boots may take a little longer. Run powercfg /hibernate on to bring it back. The options are listed in Microsoft's powercfg reference.

pagefile.sys

The page file is where Windows moves memory it can't keep in RAM. It can be several gigabytes. Leave it set to Automatically manage paging file size. Shrinking or removing it can cause apps to crash when memory runs low, and the space saved is rarely worth it.

System Restore points

Restore points live in the hidden System Volume Information folder. To see and limit their space, search for Create a restore point, select your C: drive and click Configure. The Max Usage slider sets the limit, and Delete removes all restore points for that drive.

A gentler option is in Disk Cleanup: after Clean up system files, open the More Options tab and use the System Restore and Shadow Copies button. It removes all but the most recent restore point.

Windows.old

After a major upgrade, Windows keeps your previous installation in C:\Windows.old so you can go back. It can be 10 GB or more. Remove it with Cleanup recommendations or with Disk Cleanup's Previous Windows installation(s) option. Microsoft notes that deleting it means you can no longer roll back, and that can't be undone. If you upgraded fewer than 10 days ago and might want to go back, wait.

5. A disk map for everything else

Storage settings groups space into categories and stops there. A disk map scans every folder and draws it to scale, so a 40 GB game cache or a forgotten virtual machine in your user folder stands out at once. Common finds include old node_modules folders (see deleting node_modules), game libraries, video exports and phone backups.

Free options include WinDirStat, WizTree, TreeSize Free, SpaceSniffer and freedisk.space. We compare them in WinDirStat alternatives for Windows 11.

What to leave alone

• C:\Windows, including WinSxS, Installer and System32. Clean these only with DISM or Disk Cleanup.
• Program Files folders. Uninstall apps from Settings > Apps instead.
• System Volume Information and $Recycle.Bin. Manage them from System Protection and the Recycle Bin.
• pagefile.sys and swapfile.sys.

How to choose where to start

• You want quick space with no risk: Cleanup recommendations.
• System & reserved is huge: check WinSxS, hibernation, restore points and Windows.old.
• Other or your user folder is huge: use a disk map.

Questions people ask

How do I see what is taking up space on my C: drive in Windows 11?

Open Settings, then System, then Storage, and click Show more categories. For a folder-by-folder view of the whole drive, use a disk analyzer such as WinDirStat, WizTree or freedisk.space.

Why is System and reserved so big in Windows 11?

It includes the WinSxS component store, the hibernation file, the page file, System Restore points and reserved storage for updates. Each one can be reduced with a built-in tool, never by deleting files by hand.

Can I delete the WinSxS folder?

No. Microsoft warns that deleting it can stop Windows from booting or updating. Run Dism.exe /Online /Cleanup-Image /StartComponentCleanup from an administrator Command Prompt instead.

Is it safe to delete hiberfil.sys?

Yes, if you don't use hibernate. Run powercfg /hibernate off as administrator, which removes the file and also turns off Fast Startup.

Can I delete the Windows.old folder?

Yes, through Cleanup recommendations or Disk Cleanup's Previous Windows installation(s) option. Once it is gone you can no longer roll back to your previous version of Windows.

How do I free up space taken by System Restore?

Search for Create a restore point, select your C: drive and click Configure to lower Max Usage or delete restore points. Disk Cleanup can also remove all but the most recent one.