Once the new .zip is created, follow the renaming steps in Method 1 to change the extension to .sb3 . Method 3: Using Online Conversion Tools
If you are on a mobile device (like an iPad or Chromebook) where renaming file extensions is difficult, online tools can help. convert zip to sb3
Open the Scratch Online Editor , go to , and select your new file. Method 2: Re-Zipping Extracted Files Once the new
If your sprites or sounds are missing after conversion, check the original ZIP. If the files were renamed (e.g., from a1b2...png to costume1.png ), Scratch won't be able to find them. The filenames inside the ZIP must match the references inside the project.json file. Method 2: Re-Zipping Extracted Files If your sprites
If your project is currently a full of files (like project.json and various images), you need to package them back up correctly. Open the folder containing the project files.