The fastest way to free up disk space in Windows 11 is Settings > System > Storage > Cleanup recommendations, which lists temporary files, large files and unused apps you can remove in a few clicks. Turn on Storage Sense to keep space free automatically. The twelve methods below run from the safest quick wins to bigger, more deliberate changes.
| # | Method | Typical space recovered | Risk |
|---|---|---|---|
| 1 | Cleanup recommendations | Small to large | Low |
| 2 | Temporary files | Small to large | Low |
| 3 | Storage Sense | Ongoing | Low |
| 4 | Disk Cleanup (system files) | Medium to large | Low |
| 5 | Remove Windows.old | Large | Medium (no rollback) |
| 6 | Uninstall unused apps and games | Varies | Low |
| 7 | Find and move large files | Varies | Low |
| 8 | OneDrive Files On-Demand | Large for heavy OneDrive users | Low |
| 9 | Save new content to another drive | Ongoing | Low |
| 10 | Turn off hibernation | Several GB | Medium (loses hibernate) |
| 11 | Clean up the component store | Medium | Medium |
| 12 | Compact OS | A few GB | Medium (small performance cost) |
How do you see what is using disk space in Windows 11?
Open Settings > System > Storage. Windows shows a breakdown of your system drive by category, such as Installed apps, Temporary files, Documents and System & reserved. Select Show more categories for the full list, then open any category to see exactly what is inside before you delete anything.
For other drives, scroll to Advanced storage settings > Storage used on other drives. This is where Windows reports usage for secondary SSDs, hard drives and USB drives.
What we commonly see: the "System & reserved" category alarms people because it can run to tens of gigabytes. Much of it is the page file, hibernation file and reserved storage that Windows needs for updates, so treat it as mostly fixed rather than something to hunt through.
What are cleanup recommendations in Windows 11?
Cleanup recommendations is a section in Storage settings that gathers the easiest wins in one place: temporary files, large or unused files, files already synced to the cloud, and unused apps. Go to Settings > System > Storage > Cleanup recommendations, review each list, tick what you want removed and select Clean up.
- Open Settings > System > Storage.
- Select Cleanup recommendations.
- Expand Temporary files, Large or unused files, Files synced to the cloud and Unused apps in turn.
- Tick only items you recognise and no longer need. Windows shows the space each selection frees.
- Select the Clean up button for each section.
Microsoft's free up drive space guide describes the same tool and is worth bookmarking.
How do you delete temporary files safely?
Go to Settings > System > Storage > Temporary files, wait for the scan, tick the categories you want to remove and select Remove files. Windows only lists items that are safe to delete, such as cached update files, thumbnails and delivery optimisation files. Check the Downloads box carefully, because it deletes your personal downloads too.
- Windows Update Cleanup: old update files no longer needed. Often the biggest item after a feature update.
- Delivery Optimization Files: update pieces cached to share with other PCs; safe to remove.
- Thumbnails: rebuilt automatically when you next browse folders.
- Recycle Bin: permanently deletes anything in it.
- Downloads: your downloaded files. Leave unticked unless you have checked the folder.
Cause and effect: deleting thumbnails frees space but makes picture folders open a little slower the first time, while Windows regenerates them. That is harmless, and it is the main trade-off in this list.
How do you turn on Storage Sense in Windows 11?
Open Settings > System > Storage and turn on Storage Sense, then select it to adjust the schedule. Storage Sense runs automatically to clear temporary files, empty old Recycle Bin items, tidy the Downloads folder if you allow it, and make unused OneDrive files online-only. It works on the system drive.
- Go to Settings > System > Storage and switch Storage Sense on.
- Select Storage Sense to open its options.
- Under Run Storage Sense, choose how often it runs, or During low free disk space.
- Set Delete files in my recycle bin if they have been there for over to a period you are comfortable with.
- Leave Delete files in my Downloads folder set to Never unless you use Downloads purely as a temporary space.
- Select Run Storage Sense now for an immediate clean.
Is Disk Cleanup still available in Windows 11?
Disk Cleanup is the older cleanup tool. Microsoft now directs users to Storage settings, which covers the same categories, but Disk Cleanup can still be opened on many Windows 11 PCs by searching for it or running cleanmgr. Its Clean up system files button is useful for update leftovers.
- Press Windows key + R, type
cleanmgrand press Enter. Choose drive C: if asked. - Select Clean up system files and approve the administrator prompt.
- Tick items such as Windows Update Cleanup and Temporary files.
- Select OK, then Delete Files.
If cleanmgr does not open on your build, use the Temporary files page in Settings instead; it removes the same update leftovers.
Is it safe to delete Windows.old?
Yes, once you are happy with the current version of Windows. The Windows.old folder holds your previous installation after a feature update or upgrade, so you can roll back. Delete it through Settings > System > Storage > Temporary files > Previous Windows installation(s), never by dragging the folder to the Recycle Bin.
Windows removes the folder automatically after a short rollback period, which Microsoft describes as 10 days. Removing it earlier is permanent: you can no longer go back to the previous version through Settings > System > Recovery.
Advanced nuance: after a major upgrade, Windows.old can also be the place to retrieve personal files from an older profile that did not migrate. Check C:\Windows.old\Users before you remove it.
If you recently moved to a new feature update, our guide to checking your Windows 11 version confirms which release you are on before you give up the rollback option.
How do you uninstall apps you no longer use?
Open Settings > Apps > Installed apps, set Sort by to Size (large to small), then select the three dots next to an app you no longer need and choose Uninstall. Games, video editors and older versions of creative software are usually the largest items.
Some apps keep their data elsewhere, for example game libraries on a separate drive or project files in Documents. Check the app's own settings before uninstalling if you might want that data later.
How do you find and move large files?
Use Cleanup recommendations > Large or unused files to spot big files quickly, or search File Explorer for size:gigantic to list files over 4 GB. Move what you want to keep to an external drive or another internal drive, and delete what you no longer need.
- Open File Explorer and select This PC.
- In the search box, type
size:gigantic(over 4 GB) orsize:huge(1–4 GB). - Review the results. Old videos, disc images (ISO files) and backups are typical finds.
- Cut and paste files you want to keep onto an external drive, then empty the Recycle Bin.
To stop the problem returning, go to Settings > System > Storage > Advanced storage settings > Where new content is saved and point new apps, documents, music, photos and videos at a second drive.
How does OneDrive Files On-Demand save space?
With Files On-Demand, OneDrive keeps files in the cloud and leaves a small placeholder on your PC. You still see every file in File Explorer, and it downloads when you open it. Right-click a folder in OneDrive and choose Free up space to turn local copies into online-only files.
- Cloud icon: online-only, uses no local space.
- Green tick outline: downloaded copy you can remove again.
- Solid green tick: set to Always keep on this device.
Online-only files need an internet connection to open, so keep anything you need while travelling set to Always keep on this device.
Should you turn off hibernation to free up space?
Turning off hibernation deletes hiberfil.sys, which can occupy several gigabytes on PCs with plenty of RAM. Run powercfg /hibernate off in an administrator terminal. The trade-off is losing Hibernate, and on most PCs Fast Startup too, so only do this if you never use them.
- Right-click Start and select Terminal (Admin).
- Run
powercfg /hibernate off. The file is removed immediately. - To restore it later, run
powercfg /hibernate on.
Microsoft's powercfg reference also documents powercfg /hibernate /type reduced, a middle ground that shrinks the file while keeping Fast Startup. Our comparison of sleep, hibernate and shut down helps you decide whether you need hibernation at all.
How do you safely shrink the WinSxS folder?
Never delete files from C:\Windows\WinSxS by hand. Instead, run Dism.exe /Online /Cleanup-Image /StartComponentCleanup in an administrator terminal. This removes superseded versions of Windows components that newer updates have replaced, which is the supported way to reduce the component store's size.
Microsoft warns in its WinSxS clean-up guidance that deleting files from WinSxS can leave a PC unable to boot or update. Adding /ResetBase frees more space but means existing updates can no longer be uninstalled, so use it only on a stable system.
WinSxS also looks larger in File Explorer than it really is, because many of its files are hard-linked to copies in other Windows folders and are counted twice. If DISM reports errors here, our guide to SFC and DISM scans explains the repair commands.
What is Compact OS and should you use it?
Compact OS compresses Windows system files to save a few gigabytes, which helps on small-storage laptops and tablets. Run compact /compactos:query to check its status and compact /compactos:always in an administrator terminal to enable it. There is a small processor cost to decompress files, so it suits low-capacity drives rather than well-specified PCs.
On PCs with ample free space, you will notice no real benefit, so leave it off unless storage is genuinely tight.
What should you never delete to free up space?
Do not manually delete anything inside C:\Windows, especially System32 and WinSxS, or files such as pagefile.sys and hiberfil.sys. Also avoid Program Files folders (uninstall apps properly instead) and the System Volume Information folder. Use the built-in tools above, which know what is safe to remove.
- System32: core Windows files. Deleting from it can stop Windows starting.
- WinSxS: use DISM component cleanup, never manual deletion.
- pagefile.sys: managed under advanced system settings, not deleted.
-
Windows Installer cache (
C:\Windows\Installer): needed to repair and uninstall programs.
Avoid third-party "registry cleaners" and aggressive "debloat" scripts too; they free little space and can break updates. If free space is low because the drive is simply too small, the better long-term fix is a larger SSD with a fresh installation, activated with a genuine Windows 11 Home or Windows 11 Pro key.
Frequently asked questions
How much free space does Windows 11 need?
Windows 11 needs at least 64 GB of storage to install, but a working PC needs headroom beyond that for updates, the page file and temporary files. Aim to keep at least 10–15% of your system drive free. Feature updates in particular need spare space to download and install successfully.
Why is my C drive full for no reason?
Usually it is not for no reason: common culprits are a recent feature update (Windows.old and update files), large game or video folders, a growing Downloads folder, or OneDrive files stored locally. Open Settings > System > Storage and expand each category to find what has grown.
Is it safe to delete temporary files in Windows 11?
Yes, when you use Settings > System > Storage > Temporary files or Storage Sense. Windows only lists files it can remove safely and skips anything currently in use. The one category to double-check is Downloads, which contains your own files rather than temporary system data.
Does freeing up disk space make Windows 11 faster?
It helps when the drive is nearly full, because Windows needs free space for the page file, updates and temporary data. Once you have reasonable headroom, deleting more files makes little difference to speed. Startup apps, background processes and available memory usually matter more for everyday performance.
Can I delete the Windows.old folder manually?
You should not drag it to the Recycle Bin, because many files inside are protected and the attempt often fails partway. Use Settings > System > Storage > Temporary files and tick Previous Windows installation(s), or Disk Cleanup's Clean up system files option, which removes it cleanly.
Related guides
- How to free up RAM and speed up Windows 11
- How to run SFC and DISM scans to repair Windows 11
- Sleep vs hibernate vs shut down in Windows 11
- How to show hidden files and folders in Windows 11
- How to completely wipe a hard drive in Windows 11
Links in this guide
| Link | Type | Why it helps |
|---|---|---|
| Check your Windows 11 version | Internal | Confirms your release before removing Windows.old |
| Sleep vs hibernate vs shut down | Internal | Decide whether you need the hibernation file |
| SFC and DISM scans | Internal | Repairing the component store if DISM reports errors |
| Windows 11 Home key | Internal | Genuine licence for a fresh install on a larger drive |
| Windows 11 Pro key | Internal | Genuine Pro licence for a new or upgraded PC |
| Microsoft Support: Free up drive space | External | Official cleanup recommendations guidance |
| Microsoft Learn: Clean up the WinSxS folder | External | Supported way to shrink the component store |
| Microsoft Learn: powercfg options | External | Hibernation file commands |