Planned Release Date: November 2026

About This Software

Your games are bigger than they need to be

ShelfSpace compresses installed games with the compression built into Windows, the same engine as compact.exe. Games take less space and keep running exactly as before: no repacking, no mods, nothing to extract before you play.

Why not just compact.exe or a free GUI?

The compression itself is the one built into Windows, and we don't pretend otherwise. What ShelfSpace adds is everything around it:

• An estimate for every game before anything is touched, so you don't spend an hour on a game that frees 20 MB
  
• Pause and resume: stop for the evening, continue tomorrow
  
• A tray watcher that re-compresses only the files an update rewrote, so a patch doesn't quietly undo your savings
  
• Cleanup of leftovers and shader caches from games you have already uninstalled

See the savings before anything is touched

Press Estimate and ShelfSpace samples every game you include with the real algorithm, then shows how much you can free as a low–high range. A game with nothing to gain is marked and skipped. Only then press Compress.

Fast, and it stays compressed

• Compresses with several workers in parallel, with an optional per-drive limit for HDDs
  
• Pause, resume or cancel at any moment
  
• Game updates write files back uncompressed — the optional updates watcher runs from the tray and re-compresses the changed files once the game folder has been quiet for a few minutes
  
• Large files that would not shrink are skipped after a quick trial instead of wasting minutes

Games stay intact

Files are compressed in place by the file system, and games read them normally. We ran Steam's "Verify integrity of game files" after every compress, decompress and cancel in testing, and Steam never had to re-download a file. Any game can be decompressed back to full size at any time.

More than compression

• Finds your Steam libraries automatically; any other game folder or drive can be added by hand
  
• Cleans up leftovers of uninstalled games, shader caches of removed games and GPU driver shader caches (drivers rebuild them) — listed with sizes, nothing selected by default; removal goes to the Recycle Bin, and a folder too big for it is deleted permanently
  
• Disk report: what your games take on each drive and how much can still be freed
  
• Four animated themes: Diorama, Cosmos, Liquid and Terminal
  
• 11 languages
  
• No administrator rights, no drivers, no account, no telemetry, no network access

How much will I save?

It depends on the game. In our tests with LZX, Dota Underlords freed 805 MB, Unturned 752 MB and Stumble Guys 599 MB — roughly a quarter to a third of their size — while Brawlhalla, which ships already-compressed data, freed only 22 MB. The estimate tells you which kind each of your games is before you spend any time on it.

Good to know

• Works on NTFS drives (the default for Windows drives).
  
• Games that use DirectStorage on Windows 11 are better left uncompressed — their data is meant to go to the GPU without CPU decompression.
  
• We have not tested games with anti-cheat systems. Compressed files are byte-for-byte identical when read, but try such games one at a time — you can always undo it.

AI Generated Content Disclosure

The developers describe how their game uses AI Generated Content like this:

The store artwork and some store page text were created with the help of generative AI tools and reviewed and edited by the developer. ShelfSpace itself does not generate any content with AI while it runs.