Three large hidden system files often explain missing disk space. They are not junk: Windows uses them. You can change how big they are, but the right way is through Windows settings, not File Explorer.
hiberfil.sys stores the system state when the PC hibernates and is also used by Fast Startup. pagefile.sys is virtual memory that Windows uses when RAM is under pressure and for some crash information. swapfile.sys is used by modern apps. All three are in the root of the Windows drive and are hidden by default.
The hibernation file is typically a large fraction of your installed RAM, and the page file grows with how Windows manages memory. On a small SSD they can take many gigabytes.
Yes, if you do not use hibernation. Open Terminal as administrator and run powercfg /h off. This removes hiberfil.sys and also disables hibernation and Fast Startup. To bring it back, run powercfg /h on. If you want to keep it but make it smaller, powercfg /h /type reduced is an option on versions that support it.
Leave it system managed unless you know why you are changing it. If you must adjust it, use Settings → System → About → Advanced system settings → Performance Settings → Advanced → Virtual memory. Turning the page file off can cause apps to fail or crashes to leave no information.
Do not delete these files from File Explorer or with third-party scripts, and do not try to take ownership of them. Windows recreates or locks them, and forcing it can cause problems.
Before changing system files, check the easier wins: temporary files, Windows.old, Windows Update Cleanup and large files you no longer need. See the related guides below.
Rain Cleaner (Windows 10/11, 64-bit) shows what it found, with an explanation for each item, before it removes anything. The Free version has no ads; Pro has a free 14-day trial (no card). You can do everything in this guide with Windows alone.
Last updated: 2026-10-03
Not from File Explorer. If you do not use hibernation, run powercfg /h off from an administrator terminal; Windows then removes the file itself.
Not by hand. Keep it system managed; turning it off can cause app failures or lost crash information.
Yes, it removes hiberfil.sys, which is often several gigabytes. It also turns off hibernation and Fast Startup.
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