Free JSON Formatter EN

Free JSON Formatter turns any raw JSON page into an interactive, collapsible, syntax-highlighted tree - instantly, and entirely inside your own tab.

PRIVACY, VERIFIABLE
- No ads. No affiliate code. Nothing is injected into any page you visit.
- No telemetry, no analytics, no tracking.
- Zero network requests - the extension has no server to talk to.
- One permission: "storage", used only to remember your own settings.
- Open source (MIT). Read every line: github.com/andret2344/free-json-formatter
- Under 30 kB packed. No remote code, no bundled SDKs.

These are checkable claims, not promises. The end-to-end test suite asserts that formatting a document makes no network request at all, and the privacy policy lists every single key the extension writes to your device.

FEATURES
- Automatic detection of JSON pages (application/json, .json URLs, or a plain

 of valid JSON)

- Collapsible tree with lazy rendering - multi-megabyte documents stay responsive

- Syntax highlighting for keys, strings, numbers, booleans and null

- In-tree search with match count, next/previous, and case-sensitivity toggle - it searches the parsed JSON, so it finds matches inside branches you have not opened yet

- Line numbers that stay stable when you fold, exactly like code folding

- Copy path - hover any line, copy a console-ready accessor (json.items[0].id) straight into devtools, where the document is already exposed as "json"

- Line links - click a line number to get #L21 in the address bar; the link reopens that exact line later

- Expand all / Collapse all, cancellable, plus Ctrl/Cmd+click to fold a whole level

- Formatted / Raw toggle - the original text is one click away

- Copy raw or copy re-indented JSON

- Indent guides, highlighted for the level under your pointer

- Clickable URLs inside string values

- Themes: Auto (follows your OS), Light, Dark

- Configurable indentation: 2/4/6/8 spaces, or 1/2 tabs

- Line wrapping toggle

- Settings for maximum payload size and initial tree depth - the popup never reloads your tab, so nothing on screen is thrown away

BUILT FOR BIG DOCUMENTS

Large files open at a sensible depth instead of dumping 20,000 lines on you. Branches are rendered only when you open them. Expanding a huge tree runs in batches you can cancel at any time.
Works on Chrome, Edge, Brave, and Firefox.
Source: github.com/andret2344/free-json-formatter

Issues: github.com/andret2344/free-json-formatter/issues