Use tools to dump your original discs into .iso format.

Place the chdman.exe file and the CUE or ISO to CHD.bat script into the folder where your PS2 .iso files are stored.

PS2 game discs often contain massive amounts of "dummy data." Developers used padding to fill up the physical space on a DVD. This placed data closer to the outer edge of the disc, which allowed the PS2's laser to read it faster. When ripped to a computer, this useless padding is preserved, creating bloated file sizes. Compression vs. Trimming

Excellent. It offers high compression ratios and zero in-game stutter. Compatibility: Fully supported by PCSX2 and AetherSX2. 2. CSO (CISO / Compressed ISO)

While 7-Zip shrinks games tightly for storage, emulators cannot read them actively. You have to uncompress them to play, which wastes time and CPU power. Stick to CHD or CSO.

: Use a tool called chdman (part of MAME tools) to convert ISO files to CHD. CSO (Compressed ISO) : Best for : Portable devices and some PS2 homebrew.

Many sites promise a 100MB Gran Turismo 4 . When you download it, you get a .exe installer (not a game file). This installer often contains cryptocurrency miners or ransomware.

These formats allow you to save significant space—often 20% to 50%—while remaining directly playable in emulators or via homebrew loaders.

Note: Tekken 5 compresses incredibly well because it contains a full arcade version of Tekken 1, 2, and 3 (redundant code).

: Originally nearly 4.2 GB, a losslessly compressed CHD version drops to around 2.4 GB. Heavily ripped versions (minus radio stations and cutscenes) can shrink under 600 MB.

, squeezing every megabyte possible without cutting content.

What are you playing on? (PC, Android phone, Steam Deck?) (Racing, RPG, Fighting?)

: Selecting the "Ultra" compression level in 7-Zip is the most common way to shrink a PS2 ISO for sharing. Large games like God of War II can be reduced significantly this way, though they must be unzipped to play (unless using a compatible emulator like PCSX2 which can sometimes read them directly).

When creating images, ensure the file structure remains intact so the emulator or console can read it. Best Practices

Compression algorithms identify this dummy data and remove it. They also compress audio, video, and texture files.

Do you plan to play these games on a or a modded PS2 console ?