Use . Its superior compression will give you the smallest file sizes for long-term storage, especially for games with a lot of audio.
A file that is smaller than most "scene releases" but 100% bit-perfect to the original disc. ps2 iso highly compressed high quality top
Use a batch script to convert all ISOs to CHD automatically with one click. Maxciso / CISO Tools Use a batch script to convert all ISOs
Disclaimer: Downloading copyrighted ISOs is illegal if you do not own the original disc. This article is for educational and backup purposes. A newer variant that requires less processing power
A newer variant that requires less processing power to decompress compared to standard CSO, making it useful for lower-end hardware. Recommended Tools for DIY Compression
Warning: Downloading or distributing copyrighted PS2 game ISOs without permission is illegal in many jurisdictions. Use this guide only for legally owned games or public-domain/homebrew titles.
PCSX2 nightly builds support .zst ISO compression: