Free JSON explorer, formatter, and mock REST API generator with interactive tree view and JSONPath display.
Kappafy is a free JSON explorer that turns raw JSON into an interactive collapsible tree view. Click any node to see its JSONPath, analyze document statistics, prettify or minify JSON, and generate mock REST API endpoints from your data structure. Everything runs client-side — ideal for inspecting API responses, designing schemas, and prototyping mock backends.
- Collapsible JSON tree view with color-coded data types
- JSONPath display for any selected node with copy support
- JSON statistics: total keys, nesting depth, array sizes, type distribution
- Mock REST API endpoint generation (GET, POST, PUT, DELETE)
- One-click JSON prettify and minify
- Copy formatted or minified JSON to clipboard
- Syntax-error reporting with line numbers
- Drag-and-drop JSON file upload
- Large-document handling with virtualized rendering
- 100% client-side — no data leaves your browser
- MIT licensed
- No signup, no tracking
- Pure HTML, CSS, and vanilla JavaScript
- No build step
- No external dependencies (except Google Fonts on some pages)
- Hosted on GitHub Pages with Cloudflare CDN
Kappafy is part of Zovo Tools — free developer tools by a solo developer. No tracking, no signup, no nonsense.
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MIT licensed.
Built and maintained by Michael Lip. For questions or feedback: support@zovo.one