You can also use Scratch itself to convert a ZIP file to SB3:
Solution: SB3 files cannot be encrypted. You must remove the password from the ZIP using tools like 7-Zip (Windows) or Keka (Mac) before converting. convert zip to sb3 updated
If you have 100+ ZIP files to convert, renaming manually is tedious. Use this PowerShell (Windows) or Bash (Mac/Linux) script: You can also use Scratch itself to convert
If you want to avoid manual file management, several websites offer free "ZIP to SB3" converters. However, in 2026, security warnings have increased around such tools. ⚠️ Warning: Never upload your Scratch projects to
Recommended (Safer) Online Tools:
⚠️ Warning: Never upload your Scratch projects to an unknown online converter unless you are comfortable sharing your source code and media assets. Many free tools inject ads or track user data. For school projects with student data, avoid online converters entirely and use Method 1 or 2.