— Online JSON Beautifier & Validator
Theme:
Data never leaves your browser
Paste your JSON on the left and click Format →
Input
Output

How to Use the JSON Formatter

Using this tool is simple and requires no sign-up. Just paste your JSON string into the Input panel on the left and click Format (or press Ctrl+Enter). The formatted, syntax-highlighted JSON will appear instantly in the Output panel.

Features

⚡ Instant Formatting

Beautify messy or minified JSON into a readable, indented structure in milliseconds.

✓ JSON Validation

Instantly detects syntax errors and shows the exact line and position of the problem.

⇒ JSON Minifier

Strip all whitespace to produce the most compact JSON for APIs and storage.

🎨 Syntax Highlighting

Keys, strings, numbers, booleans, and null values are color-coded for easy reading.

🔒 100% Private

All processing happens in your browser via JavaScript. No data is ever uploaded to any server.

↓ Download

Save the formatted JSON directly to a .json file with one click.

Frequently Asked Questions

What is a JSON Formatter?
A JSON Formatter (also called a JSON Beautifier or JSON Pretty Printer) takes a compact or minified JSON string and re-formats it with proper indentation and line breaks, making it easy to read and understand. It is an essential tool for developers working with APIs, configuration files, and data exchange.
Is my data safe when using this tool?
Yes. This JSON Formatter runs entirely in your browser using JavaScript. Your JSON data is never sent to any server. You can even use it offline once the page is loaded. This makes it completely safe for sensitive or proprietary data.
What is the difference between Format and Minify?
Format adds indentation and newlines to make the JSON human-readable. Minify does the opposite: it removes all unnecessary whitespace to make the JSON as compact as possible, which is ideal for sending data over a network or storing it efficiently.
Why am I getting a JSON parse error?
Common causes include: trailing commas after the last item in an object or array (not allowed in JSON), single quotes instead of double quotes for strings, unquoted property keys, or missing commas between items. The validator will highlight the exact location of the error to help you fix it quickly.
Can I format very large JSON files?
Yes. Since all processing is done locally in your browser, there is no server-side file size limit. Performance depends on your device, but modern browsers handle JSON files up to several megabytes without issues.
What is the difference between JSON and YAML?
JSON uses strict syntax with double-quoted keys, curly braces, and square brackets. YAML supports a more human-readable indentation-based format without quotes or brackets. JSON is more widely used for APIs and data exchange; YAML is popular for configuration files. Both represent the same data structures.
How do I validate JSON in Python?
Use the built-in json module: import json, then call json.loads(your_string). If valid, it returns a Python object. If not, it raises a json.JSONDecodeError with the error position. For quick browser-based validation without writing code, paste your JSON here and errors are highlighted instantly.
What does "Unexpected token" mean in a JSON error?
It means the parser encountered a character it did not expect. Common causes: a trailing comma after the last item (JSON does not allow trailing commas), single-quoted strings instead of double-quoted, unquoted key names, or JavaScript-specific values like undefined or NaN (not valid JSON). The error message includes the position to help you fix it quickly.
Can I compare two JSON objects to find differences?
Yes. Use the Diff tab. Paste your original JSON on the left and the modified version on the right, then click Compare. The tool highlights added fields in green, removed in red, and changed values in yellow. Toggle between showing all fields or only the differences.
How do I format an escaped JSON string?
Escaped JSON strings look like {\"name\":\"Alice\"} — common when JSON is stored inside another JSON field or printed in logs. Just paste the escaped string directly into the formatter. It automatically detects and unescapes it before formatting. No manual preprocessing needed.
Does this tool work offline?
Yes. Once loaded, all tools — formatter, validator, minifier, and diff — work without an internet connection. The only feature requiring network access is Share, which loads a small compression library the first time you use it.
How do I share a JSON snippet with someone?
Click Share after formatting. The tool compresses your JSON and encodes it into the URL as a ?d= parameter. Send that link — when your recipient opens it, the JSON is automatically decoded and formatted. No data is stored on any server; the entire JSON is embedded in the URL itself.
Paste JSON A and JSON B, then click Compare →
JSON A (Original)
JSON B (Modified)
Diff Result

JSON Diff — Compare Two JSON Objects Online

The JSON Diff tool performs a deep structural comparison between two JSON objects or arrays. Unlike a plain text diff, it understands JSON structure: it identifies added keys, removed keys, and changed values at any nesting depth, even when the order of keys differs.

When to use JSON Diff

  • Comparing API responses before and after a code change
  • Auditing configuration file changes in CI/CD pipelines
  • Debugging data transformations in ETL workflows
  • Reviewing JSON schema migrations
⚙ JSON Transform Tools
⇒ Minify / Compress
Remove all whitespace from JSON. Useful for API payloads and storage.
Input JSON
⇒
Minified Output
↩ Unescape JSON String
Convert an escaped JSON string (e.g. "{\"a\":1}") into a readable JSON object.
Escaped String Input
↩
Unescaped JSON
↪ Escape JSON to String
Serialize a JSON object into an escaped string. Useful for embedding JSON inside another JSON field or query parameter.
JSON Input
↪
Escaped String Output

JSON Transform Tools — Minify, Escape & Unescape

JSON Minifier / Compressor

Removes all whitespace characters (spaces, tabs, newlines) from a JSON string, reducing its size for API payloads, HTTP request bodies, and data storage.

JSON Unescape

Converts a JSON-encoded string (where quotes and special characters are escaped with backslashes) back into a readable JSON object. Commonly needed when JSON is embedded inside another JSON string field or returned as a stringified value from a database.

JSON Escape

Serializes a JSON object into an escaped string. Useful for embedding JSON inside another JSON value, URL parameters, or shell script arguments.