Brightbar JSON Viewer turns any JSON response into a fast, readable tree. It stays quick on huge files, keeps big numbers exact, and never tracks you. Free, with no account.

Tree view and formatter

  • Formats JSON automatically: application/json, the +json types, and JSON sent as text or JavaScript (JSONP included)
  • Collapsible tree with syntax colours, item counts, clickable links, readable dates and colour swatches
  • Light, dark and system themes; choose the font, text size and indentation — applied instantly
  • Raw view of the untouched response, with line numbers and wrapping

Big files without freezing

  • Opens a 16 MB, 60,000-object document in well under a second and stays responsive while you scroll, search and expand everything
  • Only the rows on screen are drawn, so a bigger file doesn’t mean a slower page

Find anything

  • Search keys and values with a live match count; Enter jumps to each match; Filter shows just the matches and their structure
  • JSONPath queries in the same box: $.data[*].email, $..price, $.items[?(@.price < 10)]
  • Table view turns an array of objects into a sortable table

Exact and correct

  • Big numbers stay exact: IDs like 149883901923910003 are shown, searched and copied as sent, never rounded
  • Invalid JSON gets an error view with the message, line and column, plus a lenient parse for comments and trailing commas
  • Copy any value as valid JSON; copy its path as JSONPath, a JS accessor or a JSON Pointer; download the document
  • Full keyboard navigation of the tree, built as an accessible tree for screen readers

A viewer page of its own

Paste JSON, open a file or drop one — JSON, JSON with comments and NDJSON — validated as you type, with Format and Minify.

Private, and you can check

No tracking, analytics, ads or donation popups, and no network requests of its own. It’s open source, and every build runs an automated check that fails if the code contains a network API, a remote address or code built from strings. Hovering an image URL shows a thumbnail loaded from that address; you can turn previews off in the options. Chrome shows “Read and change all your data on all websites” at install because recognising a JSON response means looking at every page you open; on ordinary pages the extension checks the content type and stops. See the privacy policy.

Also from Brightbar

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  • Brightbar DevTools — CSS inspector, measurements, accessibility audit and more in one extension.
  • Cookie DevTools — Edit, decode, import, protect and export cookies.