What's the difference between format and beautify?

Nothing — they're the same operation. Format / beautify / pretty-print all add indentation and newlines so JSON is readable. Minify is the opposite: it strips all unnecessary whitespace.

Online JSON Formatter & Beautifier

Paste JSON to format, beautify, pretty-print, minify, validate, or repair it — and explore it in an interactive tree viewer. All in your browser.

All processing happens in your browser. Your data never leaves your device.

JSONYard is a free online JSON formatter, beautifier, and viewer that pretty-prints, minifies, and validates JSON syntax against RFC 8259, then lets you explore the result as an interactive tree. It also repairs broken JSON (trailing commas, single quotes, comments, unquoted keys). Every operation runs entirely in your browser — your JSON is never uploaded, logged, or sent to any server.

What you can do with this JSON formatter

Format & minify

Pretty-print JSON with 2-space, 4-space, or tab indentation. Strip all whitespace to compact one line.

Validate

Catch syntax errors with the exact line and column. Click to jump to the problem.

Tree view

Explore deeply nested JSON without scrolling forever. Collapse, expand, copy paths and values.

Repair broken JSON

Trailing commas, single quotes, comments, unquoted keys — Repair mode fixes them and tells you what changed.

Large files

Files over 200KB are parsed off-thread in a Web Worker so the UI never freezes.

Share via URL

Encode small payloads in the URL hash. Nothing is sent to a server — the hash stays in your browser.

How to format JSON online

Paste, drop, or upload your JSON into the left pane of this online JSON formatter.
Click Format (or press Ctrl+Enter) to pretty-print, or Minify (Ctrl+M) to compact it.
Switch the right pane to Tree view — a built-in JSON viewer for exploring nested structures.
If the input is broken, click Repair — JSONYard will fix what it can and explain the changes.
Copy, download, or share the result.

Why pretty-print JSON?

JSON sent over the wire is usually minified — every byte counts. The moment a human has to read it, that compactness becomes the problem: nested objects collapse onto one line, errors hide between unbalanced brackets, and diff tools become useless. A JSON beautifier (also called a pretty-printer) reverses minification — it inserts newlines and consistent indentation so the document's shape matches its meaning. JSONYard's formatter gives you 2-space, 4-space, or tab indentation, optionally sorts keys, and validates while it formats so syntax errors surface at the exact line and column. If you need to compare two payloads after formatting, our structural JSON diff ignores whitespace and key order so a reformat doesn't show up as a "change".

JSON formatter, beautifier, validator, viewer — what's the difference?

All four labels describe overlapping things, which is why most online JSON tools ship them together. A JSON formatter or JSON beautifier adds indentation. A JSON validator checks that the input is well-formed JSON per RFC 8259 — JSONYard's JSON validator reports the exact line and column of any error. A JSON viewer renders the document as a collapsible tree so you can drill into deeply nested structures. JSONYard combines all four on this page; the dedicated tool pages add specialised capabilities like validating JSON against a JSON Schema or testing JSONPath expressions.

Frequently asked questions

Is my JSON sent to a server?

No. JSONYard runs entirely in your browser using JavaScript. You can confirm this yourself by opening your browser's developer tools, switching to the Network tab, and watching for outbound requests as you paste and format. There aren't any.

How big a file can I format?

Files larger than about 200KB are parsed in a Web Worker, which keeps the UI responsive while the worker handles parsing. We've tested 50MB+ files comfortably. Beyond that, you're bounded by your browser's available memory.

What does "Repair" do?

Repair mode accepts common JSON-ish inputs and fixes them: trailing commas at the end of arrays and objects, single-quoted strings, // line and /* block */ comments, and unquoted keys. After repairing, it shows a list of what it changed.

Can I share my formatted JSON via a link?

Yes — the Share button encodes small payloads in the URL hash (after #). Because URL hashes are never sent to the server, the data still stays in the browser. Large payloads can't be shared this way — use Download instead.

What's the difference between format, beautify, and pretty-print?

Nothing. All three are names for the same operation — adding indentation and newlines so JSON is readable. Minify is the opposite: it strips all unnecessary whitespace so the JSON takes up less space on the wire.

Do you use cookies or tracking?

We use localStorage to remember your theme and indent preferences. We don't set tracking cookies, fingerprint your browser, or analyze your JSON content. If we add ads in the future, we'll display a consent banner first as required by law in the EU and California.

Why does my number lose precision after formatting?

JavaScript's JSON.parse converts every number to a 64-bit float. Numbers larger than 2⁵³−1 (about 9 quadrillion) lose precision. If you're working with big IDs, transmit them as strings — that's a JSON design choice, not a bug in any formatter. See our note on JSON number precision and the BigInt problem.

Is this JSON formatter free? Is there a download?

It's completely free, with no signup, no rate limits, and no download. JSONYard is a static web app — open the URL and use it. Because it runs in your browser, it works offline once the page has loaded.

How do I beautify or pretty-print JSON from the command line?

For one-off use, paste into this online JSON formatter. For scripting, python -m json.tool file.json, jq . file.json, or Node's JSON.stringify(obj, null, 2) all pretty-print. Our JSON formatting standards post covers indentation choices.

Keyboard shortcuts

Ctrl+Enter — Format / Beautify / Pretty-print
Ctrl+M — Minify / Compact
Tab in the input — insert two spaces