Best Free Alternatives to JSON Formatter in 2026

Free block-based programming platform and online community for creating interactive stories, games, and animations.

Research-based interactive science and math simulations for exploring STEM concepts through virtual experiments.

Front-end development playground and social coding environment for HTML, CSS, JavaScript, live previews, and sharable experiments.

Advanced blocks-based programming language from UC Berkeley for teaching real computer science concepts beyond beginner block coding.

Open-source blocks-based programming library for building custom visual coding editors and educational coding experiences.

Former collaborative web coding and hosting platform; now mainly a legacy reference after shutdown of hosting and core service access.

Free graphing and math activity platform with graphing, geometry, 3D, and classroom tools for visual math learning.

Education-focused browser coding environment for Python, HTML, and shareable interactive code, but scheduled to shut down in early August 2026.

Free Autodesk web app for beginner-friendly 3D design, electronics simulation, and coding-based STEM projects.

Coding education platform for kids with block coding, Python, JavaScript, game creation, Minecraft, robotics, and STEM pathways.

Cloud development platform for full-stack web projects, rapid prototyping, collaboration, and shareable dev environments.

Classic browser code playground for HTML, CSS, and JavaScript snippets, demos, experiments, and bug reproductions.