Because the format is built on ZIP compression, the conversion process is lossless, meaning the original data remains intact without any degradation in quality. How to Convert ZIP to SB3 Manually
: If Scratch fails to open the file, re-compress the assets using a standard tool like Asset Quality
: Inside the ZIP, costumes and sounds are stored with randomized names but retain their original quality. This allows users to extract high-quality assets directly from a project.
: Developers often "unzip" the .sb3 file to edit the raw project.json code using text editors or external tools before re-zipping it back to the .sb3 format for use in Scratch. "Extra Quality" and Preservation Features
Change .zip to .sb3 .