How to Free Up Disk Space on Windows Without Deleting Files

A full Windows drive is rarely full of your files. On a typical machine, 20 to 60GB is occupied by Windows itself keeping things “just in case” — update backups, rollback images, restore points, a hibernation file and years of temporary data.

All of it is removable with built-in tools, and none of the steps below touches a document, a photo or an installed program.

See the breakdown first

Settings → System → Storage. Wait for it to finish calculating, then look at the category list: Apps, Temporary files, Documents, Pictures, Other, System & reserved.

Click Show more categories for the full list. Note the two or three largest before you start — it tells you whether you are dealing with Windows overhead or with your own files, and the rest of this guide addresses the first.

Clear temporary files — the big one

This single screen holds the largest wins on most machines.

Settings → System → Storage → Temporary files. You get a checklist with sizes next to each entry. The ones that matter:

Two warnings on that list.

Downloads is unticked by default and should stay that way until you have looked in the folder. Windows treats it as temporary; you may not.

Previous Windows installation(s) is your rollback path after a feature update. Windows keeps it for 10 days and then deletes it automatically. Delete it manually only once you are confident the current version is working.

Tick what you want, click Remove files, and give it a few minutes.

Turn on Storage Sense so it stays clean

Storage Sense automates the above on a schedule, which stops you repeating this in six months.

Settings → System → Storage → Storage Sense → turn it on, then click through to configure:

• Run Storage Sense — During low free disk space, or Every week
• Delete files in my recycle bin if they have been there for over — 30 days
• Delete files in my Downloads folder if they have not been opened for — Never, unless you genuinely want that

That last setting is the one people regret. Left at 30 days it will quietly delete things you downloaded and meant to keep.

Reclaim the hidden system files

These do not appear in the Storage screen at all.

System Restore

Restore points are useful and they are also allowed to consume up to 10% of the drive by default — 50GB on a 500GB SSD.

1. Press Win+R, type sysdm.cpl, press Enter.
2. System Protection tab → select your system drive → Configure.
3. Drag Max Usage down to 3–5%.
4. Click Delete to remove existing restore points if you need space now.

Keep protection on. Reducing the allocation is sensible; turning it off removes a genuinely useful recovery option.

Hibernation

hiberfil.sys is sized at roughly 40% of your installed RAM and sits on the system drive permanently — 12.8GB on a 32GB machine.

If you never hibernate, open Terminal as administrator and run:

powercfg /hibernate off

The file disappears immediately. Note that this also disables Fast Startup, which depends on the same mechanism, so on a laptop the trade is usually not worth it. To restore it: powercfg /hibernate on.

The WinSxS component store

This is where Windows keeps component versions for updates and repair. It looks enormous in Explorer — 10GB or more — but much of that is hard links counted twice, so the real figure is smaller.

Never delete from it manually. Clean it properly:

DISM /Online /Cleanup-Image /StartComponentCleanup /ResetBase

/ResetBase removes superseded update components, which means you can no longer uninstall individual updates. On a stable system that is fine and it often recovers 3–8GB.

Find what else is actually large

Once the Windows overhead is gone, anything remaining is yours — and the Storage screen is not good at pinpointing it.

WinDirStat or WizTree (the latter is much faster, because it reads the filesystem table directly) draws a treemap of your drive so a single 40GB folder is immediately visible.

The usual finds:

• Game installations — 50–150GB each. Steam, Epic and Xbox all let you move a library to another drive rather than deleting it.
• C:\Users\[you]\AppData\Local — application caches. Browsers, Discord, Teams and Spotify are the big ones. Check AppData\Local\Temp and clear it.
• OneDrive locally-available files — right-click the OneDrive folder → Free up space to make them cloud-only while keeping every file accessible.
• Old iPhone backups — AppData\Roaming\Apple Computer\MobileSync\Backup, frequently 20GB+ per device.
• Docker, WSL and virtual machines — a WSL distribution’s virtual disk grows and never shrinks on its own.

Uninstall properly

Settings → Apps → Installed apps, sorted by size. Beyond the obvious, two categories are worth attention:

• Manufacturer bloatware — trial antivirus, “PC health” suites, bundled media software. These cost disk space and startup time both.
• Duplicate runtimes — multiple Java versions, or many Visual C++ Redistributables. Leave the Redistributables alone; applications depend on specific versions.

Compact OS, if you are desperate

On a small drive — the 64GB and 128GB eMMC tablets and budget laptops — Windows can compress its own system files:

compact /compactos:always

This recovers 2–4GB at a small CPU cost when reading system files. On a modern machine with a fast CPU the cost is not noticeable, and on a machine with room to spare it is not worth doing.

What not to do

• Do not delete pagefile.sys or disable virtual memory. With limited RAM this produces out-of-memory crashes, not speed.
• Do not delete folders in C:\Windows manually. Use DISM and the Storage screen; they know what is safe.
• Do not run “PC cleaner” suites. Everything above is built into Windows, and the cleaners add a background process and frequently bundle worse.
• Do not delete C:\Windows\Installer. It looks like leftover installers and is not — removing it breaks repair and uninstall for the affected programs.
• Do not compress the whole drive with folder compression. Different from CompactOS, and it slows everything down for a modest gain.

Realistic expectations

On a Windows 11 machine a year or two into use that has had a feature update, clearing temporary files plus reducing the restore allocation typically recovers 25–50GB in under fifteen minutes. Previous Windows installations and Update Cleanup are usually most of it.

Aim to finish above 15% free on the system drive. Below roughly 10%, Windows starts struggling with updates and paging, and the machine feels slow for reasons that look unrelated to storage — the diagnosis for that is in why Windows is slow.

If the drive fills again within months, something specific is growing. A treemap tool run once a quarter finds it faster than any cleanup routine.