Format, validate and explore JSON right in your browser. Paste it, drop a file or load it from a URL: the formatter pretty-prints it, points out syntax errors, shows it as a tree and compares two documents side by side. It is free, needs no sign-up, and your JSON is never uploaded.
Add to Chrome Free: formats JSON pages right in the tab.
Pretty-print minified or messy JSON with consistent indentation. JSON you paste or drop is formatted automatically.
See at a glance whether the JSON is valid. Errors show the parser's message with the line and column of the problem.
Several JSON values in a row are recognized instead of cut off, and one click wraps them into a single array.
Expand and collapse objects and arrays, open the tree to a chosen depth, and copy any value or its path.
Find keys and values in the text or the tree, with highlighted matches and a case-sensitive mode.
The Diff tab marks added, removed and changed values between two JSON documents. Filter by change or hide unchanged keys.
Strip whitespace for the smallest output, or sort object keys alphabetically at every level. Arrays keep their order.
Long numbers keep every digit: 12345678901234567890 is
not rounded, and 1.50 is not rewritten as
1.5.
Open files up to about 10 MB: formatting runs in a background worker, and the tree renders only the rows on screen.
Step back through the last 30 formatted, minified or sorted versions of your JSON. The history stays on your device between visits.
Open a file or JSON from a URL, download the result as a
.json file, or copy a link that contains it.
There is no backend: your JSON is processed in the browser. No ads, no account, and after the first visit it works offline.
Formats JSON pages and API responses right in the tab, opens the same formatter from the toolbar or side panel, and shows a page's WebSocket messages as JSON.
.json file onto it, or
load it from a URL.
No. Formatting, validation and diffing run in your browser, and there is no backend to send data to. Load from URL fetches the address you enter; if that server blocks direct requests, the request is retried through a public CORS proxy, so open anything sensitive from a file instead. See the privacy policy for details.
Paste it into the editor. The status bar shows Valid JSON or Invalid, and for invalid JSON the editor shows the parser's error message with the line and column of the problem.
Files up to about 10 MB. Formatting runs in a background worker, and the tree view renders only the rows on screen, so large documents open and scroll without freezing the page.
No. Numbers keep the exact digits you pasted. Big integers such as
12345678901234567890 are not rounded, and values like
1.50 or 1e21 are not rewritten, as they would
be after a plain JSON.parse.
Open the Diff tab and paste one document on each side. The tree below marks added, removed and changed values; you can filter by change type or hide unchanged keys.
Yes. Put the URL-encoded JSON after #json=, for example
https://json.fedrr.com/#json=%7B%22id%22%3A1%7D. The page
formats it on load and clears it from the address bar, and Export →
Share link builds such a link for you. The part after #
never reaches a server, but anyone with the link can read the JSON.
Yes. Each Format, Minify, Sort Keys and auto-format on paste saves a snapshot, up to 30 of them and 5 MB in total. Undo steps back to the previous snapshot, and History lets you jump to any of them. Snapshots are kept on your device between visits.
Yes. After the first visit your browser keeps a copy of the formatter, so it opens and works without a connection. Loading JSON from a URL still needs the network.
Yes. JSON Formatter & Viewer for Chrome turns JSON pages and API responses into a readable tree right in the tab, on demand or automatically on sites you choose. It also opens the same formatter from the toolbar or in the side panel, and adds a WebSocket tab that shows a page's messages as formatted JSON. It is free on the Chrome Web Store.
Yes. There are no ads, no account and no paid plan.