You cannot convert a ZIP file to CHD directly. The proper workflow is to extract the disc image from the ZIP archive and then convert that image to CHD. The following tools are needed for the job:

Simplifies multi-file arcade card games. 3DO & Philips CD-i: Cleans up messy directory structures. Conclusion

This public link is valid for 7 days and shares a thread, including any personal information you added. This link or copies made by others cannot be deleted. If you share with third parties, their policies apply. Can’t copy the link right now. Try again later.

: A popular, user-friendly GUI for batch processing. You can find community guides and downloads on Retro Game Corps .

Note: This paper assumes lawful ownership of any software disc images being converted. The techniques described are intended for personal backup and preservation under applicable copyright laws.

In the ecosystem of disc-based emulation (e.g., PlayStation 1, Sega CD, Dreamcast, PSP), users frequently encounter game files packaged as ZIP archives. ZIP is a lossless, general-purpose compression format that reduces file size for storage and download. However, emulators do not typically run disc images directly from ZIP files without first extracting the contents to a temporary directory. This process consumes time and temporary storage.

While ZIP compression works well for cartridge-based roms (like NES or Genesis), it is highly inefficient for disc images. Enter CHD (Compressed Hunks of Data). Originally developed for the MAME project, CHD has become the gold standard compression format for disc-based retro gaming.

Put all of your game ZIP files into a single folder. Copy chdman.exe into this exact same folder. Step 2: Create the Batch Script

for /r %%i in (*.zip) do chdman createcd -i "%%i" -o "%%~ni.chd" pause Use code with caution. Save the file as convert.bat in that same folder.

What are you running? (Windows, macOS, Linux, or SteamOS?)

Disc games often consist of multiple files (such as a .cue sheet paired with several .bin tracks for audio). A CHD file merges all of these loose tracks into a single, clean file per game, eliminating directory clutter. Step 1: Extract Your ZIP Files First