How do I check if my JSON is valid?

Paste your JSON into the input box and click 'Validate' or 'Format / Beautify'. If the JSON is invalid, the tool shows an error message with the exact line and column number where the problem occurs.

What does 'Unexpected token' mean in JSON?

This error means the JSON parser found a character it didn't expect at a given position — often a trailing comma, a missing quote, a missing comma between items, or single quotes instead of double quotes. Our validator reports the exact line and column so you can fix it quickly.

Can I view JSON as a tree or collapsible structure?

Yes. Switch to 'Tree View' after formatting valid JSON to get an interactive, collapsible tree where you can expand and collapse objects and arrays to explore deeply nested data.

What is the difference between formatting and minifying JSON?

Formatting (beautifying) adds indentation and line breaks to make JSON human-readable. Minifying removes all unnecessary whitespace to make the JSON as compact as possible — useful for reducing payload size in production.

Can I sort JSON object keys alphabetically?

Yes. Enable the 'Sort keys' option before formatting or minifying. All object keys at every level will be reordered alphabetically, which is useful for comparing JSON files or producing deterministic output.

Free Online Tool

JSON Formatter & Validator

Q: How do I minify JSON?

Paste valid JSON into the input box and click 'Minify'. The tool removes all unnecessary whitespace and line breaks, producing the smallest possible representation — ideal for APIs and config files.

Beautify, minify, and validate JSON instantly — with precise line & column error details and an interactive tree view. 100% private, runs entirely in your browser.

100% Private Instant Validation Tree View Format & Minify Line & Column Errors

Indent:

Sort keys A–Z

Input JSON

Result

How It Works

Four simple steps to format and validate any JSON

Paste your JSON

Paste or type JSON into the input box, or click "Load Sample" to try the tool with example data.

Choose options

Pick 2/4-space or tab indentation, and optionally enable "Sort keys" to alphabetize object keys at every level.

Format, minify or validate

Click Format to beautify, Minify to compact, or Validate to check syntax only — instantly, in your browser.

Explore & export

Switch to Tree View to explore nested data, or copy the result and download it as a .json file.

Why Use Our JSON Formatter?

Accurate, fast, and privacy-first JSON tooling without leaving your browser.

100% Private

Your JSON never leaves your device. All parsing, formatting, and validation happens locally in your browser.

Precise Error Details

Invalid JSON shows the exact line and column number, plus a code snippet, so you can fix syntax issues fast.

Interactive Tree View

Explore deeply nested objects and arrays with a collapsible, color-coded tree — perfect for large API responses.

Format & Minify

Beautify JSON with 2/4-space or tab indentation for readability, or minify it to the smallest size for production.

Sort Keys A–Z

Recursively sort all object keys alphabetically for deterministic, diff-friendly output across nested structures.

Free Forever

No account, no subscription, no usage limits. Format and validate as much JSON as you want — always free.

Frequently Asked Questions

Common questions about formatting and validating JSON

A JSON formatter takes raw or minified JSON text and rewrites it with consistent indentation and line breaks, making it easier to read and debug. Our tool also validates the syntax as you format.

Paste your JSON into the input box and click "Validate" or "Format / Beautify". If it's invalid, the tool shows an error message with the exact line and column number where the problem occurs.

This means the parser found a character it didn't expect at a given position — often a trailing comma, missing quote, missing comma between items, or single quotes instead of double quotes. The validator reports the exact line and column.

Paste valid JSON and click "Minify". The tool removes all unnecessary whitespace and line breaks, producing the smallest possible representation — ideal for APIs and config files.

No. All formatting, validation, and minification happens locally in your browser using JavaScript's built-in JSON parser. Your data never leaves your device.

Yes. Enable "Sort keys A–Z" before formatting or minifying. All object keys at every level are reordered alphabetically — useful for comparing JSON files or producing deterministic output.