Introduction: How to Compress a .ISO to a .CSO (PSP Game)

Picture of How to Compress a .ISO to a .CSO (PSP Game)

This instructable will teach you how to compress an .iso file to a .cso file. Using .cso files saves space on your PSP. This can only be done if you are running custom firmware.

This is only for backups of a PSP game you OWN and not DOWNLOADED.

Step 1: Obtain a .ISO

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To obtain a rip the umd of the game you own and then archive it as a .iso. I suggest using Active ISO File Manager 2. This can be downloaded for free at.

Here is a tutorial that I wrote that will help you better understand how to use Active ISO File Manger 2

I am using a copy of Star Wars Battlefront 2. (That I own)

Step 2: Download PSP ISO Compresser V1.4

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PSP ISO Compresser v1.4 can be downloaded for free at

Step 3: Convert

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Select 'Compress ISO->CSO' on PSP ISO Compresser v1.4. Now input the location of your .iso and press compress.

Step 4: Now Play!

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Just place the .cso into your ISO folder in your PSP. Now go to the game selection on your PSP and play it.



dmenezes (author)2011-10-18

can i convert a iso file to gba file..please let me know

Steamdnt (author)2009-06-11

I already posted this, A long time ago

Cyberscann54 (author)Steamdnt2010-10-14

you may have done a instructable on the same subject but the software is different and has a lot more options and easier to use

flamtz (author)2009-05-25

Good tutorial, now I know how to download those... oh wait did I just say that? No... what I mean is how big are the cso's?

Ikotoo (author)flamtz2009-05-25

Thanks. The size of the .cso depends on the game but .cso are always smaller then the .iso that you compressed it from. Usually They decrease in size by about 15-30%. cheers.

About This Instructable




Bio: Hey I'm Ikotoo I make many things out of duct tape such as backpacks, hats, wallets, pins, neck ties and bow ties at a ... More »
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