JSON (JavaScript Object Notation) is a lightweight, human-readable data format used to exchange data between servers, APIs, and applications.

How do I validate JSON?

Paste or upload your JSON — this tool validates it live as you type and shows the exact line and column of any syntax error.

Do you upload my JSON?

No. All parsing, formatting, and conversion runs entirely in your browser. Nothing is ever uploaded, logged, or stored.

Can I format large JSON files?

Yes. The tool handles files up to ~5 MB comfortably in most modern browsers. Very large payloads are parsed with the browser's native JSON engine for maximum speed.

Can I upload JSON files?

Yes — click Upload, drag & drop a .json file onto the input area, or paste the contents directly.

Can I convert JSON to CSV, YAML, or XML?

Yes. Once your JSON is valid, use the toolbar buttons to instantly convert it to CSV, YAML, or XML.

Developer Tools · Available

JSON Formatter

Format, validate, and minify JSON with syntax highlighting.

Nothing uploaded Instant validation Works offline RFC 8259 compliant

Privacy first: Your JSON is processed entirely in your browser. Nothing is uploaded or stored.

Indent

Input JSON

Awaiting input…

Output JSON

Validation

Paste or upload JSON to validate.

Statistics

Statistics appear once JSON is valid.

Shortcuts: Ctrl+Shift+F Format · Ctrl+Shift+M Minify · Esc Exit fullscreen

What is JSON?

JSON — JavaScript Object Notation — is the most widely used data interchange format on the web. It's plain text, language-independent, and human-readable, which makes it the default choice for REST APIs, configuration files, log payloads, and messaging systems.

A JSON document is built from six types: objects, arrays, strings, numbers, booleans, and null. Correct nesting and quoting are essential — a single missing comma or bracket makes the entire document invalid.

Why formatting improves readability

Minified JSON is efficient for transport but nearly impossible to read. Formatting adds consistent indentation and line breaks so you can quickly scan nested structures, diff two payloads, or spot the exact field causing a bug. Sorting keys alphabetically makes structural comparison even easier.

Why validation matters

A JSON parser is strict by design. One trailing comma, unquoted key, or stray character will crash a downstream service. Validating before you ship saves hours of debugging — this tool pinpoints the exact line and column so you can fix it in seconds.

Privacy by design

Everything runs in your browser. There is no server, no upload, no analytics on the data itself. Close the tab and your JSON is gone — making this tool safe for API keys, customer records, or any confidential payload.

Features

✓Free Forever
✓Browser Based
✓No Login
✓No Registration
✓Instant Validation
✓Syntax Highlighting
✓Tree View & JSONPath
✓Convert to CSV / YAML / XML
✓Escape / Unescape
✓Keyboard Shortcuts
✓Fullscreen Editor
✓Mobile Friendly

How to use JSON Formatter

1
Paste JSON into the input editor, upload a file, or drag & drop.
2
Watch live validation — the badge shows Valid or Invalid with the error location.
3
Choose 2 spaces, 4 spaces, or tabs, then click Format, Minify, or Sort Keys.
4
Switch to Tree view to explore nested data and copy any JSONPath.
5
Copy the formatted output or download it as formatted.json.