Free online tool
JSON Editor, Formatter & Viewer
Edit, format, minify, validate, and browse JSON in Code or Tree mode. Runs in your browser. Share makes a short link like /j/aB3xK9m2 that fits in WhatsApp. No account.
Format & minify
Pretty-print for reading, or compress to a single line for APIs and configs.
Code and Tree
Fold JSON like an IDE, or expand and collapse nodes like a structured explorer.
Private by design
Editing stays in your browser. Share creates a short /j/ link that fits in WhatsApp.
How to use this JSON tool
- 1. Paste or type JSON into the editor (Code mode).
- 2. Use Format or Minify, then Validate to confirm the document.
- 3. Switch to Tree to expand and collapse objects and arrays.
- 4. Copy, Download, or Share a link that restores the same payload.
Frequently asked questions
- Is this JSON editor free?
- Yes. Format, minify, validate, tree view, copy, download, and share all run free in your browser.
- Does Cognitain store my JSON on a server?
- Editing stays in your browser. Share creates a short /j/ link so the chat does not fill with a giant URL.
- Can I view JSON as a tree?
- Yes. Switch to Tree mode to expand and collapse objects and arrays, with Expand all and Collapse all.
- How is this different from the Flow-UI playground?
- This page is a general JSON editor and formatter for everyday work. Flow-UI is coming soon; you can join its waitlist or open an early glimpse from Cognitain.
Flow-UI is coming soon
Flow-UI turns server JSON into native SwiftUI. It is not generally available yet. Join the waitlist for contributors or app builders, or peek at an early glimpse.