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Preview of Free JSON Formatter

Free JSON Formatter by Andret2344

Fast, private JSON viewer. Collapsible tree, syntax highlighting, search. No telemetry, no external requests.

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About this extension
Ever clicked a link and landed on a wall of raw, unformatted JSON? A single line thousands of characters long, no indentation, impossible to read? Free JSON Formatter fixes that instantly.

The moment a JSON page loads, this extension replaces the raw text with a clean, interactive tree you can actually read, explore, and search. No copy-pasting into an online tool. No sending your data to some website. It just works, right there in your tab.

WHAT IT DOES
Free JSON Formatter automatically detects when a page is JSON - any .json URL, an API response, a raw endpoint - and turns it into a structured, collapsible tree view. Objects and arrays become foldable nodes, so you can drill into exactly the part you care about and hide the rest.

WHY YOU'LL WANT IT
* Read JSON the way it was meant to be read - indented, color-coded, and structured instead of one endless line.
* Find anything fast - built-in search highlights every match as you type, with an optional case-sensitive toggle.
* Collapse the noise - expand or collapse the whole tree with one click, or fold individual branches to focus.
* Grab what you need - copy the original raw JSON, or copy a cleanly re-indented "pretty" version, in a single click.
* Make it yours - choose your indentation (spaces or tabs), toggle line wrapping for long values, and pick an Auto, Light, or Dark theme that matches how you work.
* Jump straight to links - URLs inside your JSON are clickable.
* Switch views instantly - flip between the formatted tree and the original raw text whenever you want.
* Stay fast on huge payloads - a size limit you control keeps your browser responsive, with a clear warning on very large files.

BUILT FOR PEOPLE WHO WORK WITH APIs
Developers, QA engineers, data folks, and anyone who reads API responses all day. If you live in browser tabs full of JSON, this saves you a hundred tiny annoyances a day.

PRIVACY IS NOT A FEATURE - IT'S THE FOUNDATION
Most "free" tools pay for themselves by watching you. This one doesn't.
* No telemetry. No analytics. No tracking. Not now, not ever.
* No external network requests - your JSON never leaves your browser. Everything is processed locally on your machine.
* Minimal permissions - it asks only for "storage", used solely to remember your own settings. Nothing else.
* Open source under the MIT license, so anyone can verify exactly what it does.

Your data is yours. This extension never sees it, sends it, or stores it anywhere but your own tab.

Install Free JSON Formatter and never squint at raw JSON again.
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Permissions and data

Required permissions:

  • Access your data for all websites

Data collection:

  • The developer says this extension doesn't require data collection.
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Version
0.2.1
Size
35.72 KB
Last updated
19 hours ago (Jul 13, 2026)
Related Categories
  • Web Development
License
MIT License
Version History
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  • dark mode
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