Select the file and press Return on your keyboard to edit the name. Replace .zip with .sb3 at the end of the file string.
One day, the Scratch Council decided that every project needed a sleek new outfit called an . Pixel was excited but nervous. He was currently just a humble collection of files sitting in a standard .zip archive.
Numerous SVG, PNG, and WAV files representing the assets (costumes and sounds), usually renamed to long strings of letters and numbers (MD5 hashes).
If you have the project.json and assets, you can often simply re-zip them, but they must be structured correctly. Ensure your project.json file is in the root of the folder.
If you manually edited the project.json file while it was unzipped, a single missing comma, bracket, or quotation mark will prevent Scratch from reading the code. Paste your JSON data into a free online JSON validator to ensure your syntax is completely error-free before converting it back to SB3. 3. Missing Assets Zip To Sb3 Converter
If you are working on a school Chromebook or a device that restricts file renaming, online conversion tools are your best alternative.
An is essentially a renamed ZIP archive containing the code (as a project.json file), images, and sounds of a Scratch 3.0 project. Because of this shared structure, converting a ZIP to SB3—or vice versa—is a common task for developers who want to modify assets or fix corrupted project files. Key Conversion Methods
The tool is particularly valuable when you need to distribute your projects to people who don't have Scratch installed. Generated HTML files can be opened in any modern browser, including on mobile devices.
Sometimes, a project is exported, shared, or packed into a raw ZIP format, making it unusable in the Scratch editor. This is where a becomes essential. Select the file and press Return on your
When re-zipping edited Scratch assets, people often zip the parent folder instead of the files themselves.
: Ensures the project.json file is present at the root, as this contains all the code and project logic.
To help you get your Scratch project up and running smoothly, tell me:
Are you encountering a specific when trying to load your file? Pixel was excited but nervous
Since an SB3 file is just a renamed ZIP file, the easiest solution on Windows and macOS is to change the extension directly. On Windows: Open File Explorer.
Select all the individual files (not the parent folder), right-click, and choose "Compress to ZIP file".
If you prefer to have complete control over the process or need to convert files without an internet connection, manual conversion is straightforward once you understand the file structure.
An .sb3 file is actually a hidden ZIP archive. If you take any working Scratch 3.0 project ( .sb3 ) and manually change the file extension to .zip , your computer can extract it like a regular folder. Inside, you will find: