JSON Tutorial

This article or section is undergoing major changes and may be incomplete. Please avoid making large edits to this page until this template has been removed. (January 2025)

This article or section documents the current version of Scratch (version 3.0). For this article in Scratch 2.0, see JSON Tutorial (2.0).

Warning:

Modifying the JSON code of a project could break it, so making a backup is recommended.

This is a tutorial for modifying the JSON code of a Scratch 3.0 project.

Showing File Extensions

Scratch project files are saved with the .sb3 file extension. Ignoring this extension, the project file is a ZIP archive containing the project.json file and the sound and image resources. The project file can be treated like a ZIP archive to allow modification of project.json by simply changing the file extension. Therefore, Windows and Mac users must make the following changes to unhide file extensions:

Tutorial

This tutorial is intended to give first-timers a look into the potential usefulness of "hacked blocks" and to make them more comfortable with JSON modification. The goal is to add the While () block to a project.

Firstly, start out with a new project. To make JSON editing easier, create some sort of structure that can be modified, rather than writing fresh JSON code by hand. Place the following script:

when gf clicked
repeat until <(timer) < (2)>
move (10) steps
end

Then, save the project to your computer.