To convert a file to an (Scratch 3.0 project) file, you primarily need to change the file extension. This works because an file is essentially a renamed ZIP archive containing a project.json file and various asset files (images and sounds). Step-by-Step Conversion Prepare the ZIP
: Locate your new .zip file. Right-click it, select Rename , and change the .zip ending to .sb3 . Confirm the change when prompted by your operating system.
By default, modern operating systems hide file extensions, which prevents proper renaming.
: Select all internal assets and the JSON file, then compress them into a standard ZIP archive. convert zip to sb3 updated
The ZIP contained a folder. Use Method 2 (re-compress only the inner contents). Ensure there is no __MACOSX folder (Mac metadata), which breaks SB3. Remove it before re-zipping.
The project will load fully into the workspace, allowing you to alter scripts, test animations, and run the project locally. Troubleshooting Conversion Issues
Note: If you do not see the .zip extension on Windows, open File Explorer, go to the tab, and check the box for File name extensions . Common Issues and Troubleshooting To convert a file to an (Scratch 3
Before learning how to convert files, it's crucial to understand the relationship between the two formats.
The ZIP file might be damaged. Try re-downloading or re-compressing the project.
This updated guide explains the fastest, safest methods to convert ZIP files back to .sb3 format, covering both online and manual techniques as of mid-2026. What is a .sb3 File? An .sb3 file is actually a renamed ZIP archive containing: : The core code structure. Asset Files : Costumes (PNG/SVG) and Sounds (WAV/MP3). Right-click it, select Rename , and change the
: Go to the Scratch Editor , click File > Load from your computer , and select your new .sb3 file to ensure it opens correctly. Why this works
Before starting the conversion, it helps to understand what an .sb3 file actually is. If you change the file extension of any .sb3 file to .zip and extract it, you will find the following core components: