DevTools

JSON Formatter

Prettify, minify, validate and explore JSON with syntax highlighting.

Input JSON

Output

Formatted JSON will appear here

JSON Formatter and Validator

Paste any JSON string and instantly prettify it with configurable indentation, minify it to a single line, or validate the syntax with precise error reporting. The built-in syntax highlighter uses a lightweight custom tokeniser (not Prism.js) for fast rendering even with large JSON objects.

Frequently Asked Questions

What is a JSON formatter?
A JSON formatter takes raw or minified JSON and outputs it with proper indentation and line breaks, making it easy to read and understand the structure.
Is my JSON data safe?
Completely. All JSON processing happens in your browser using JavaScript. Your data is never sent to any server.
Can it handle large JSON files?
Yes, the formatter uses efficient parsing and a custom tokeniser to handle large JSON without blocking the browser.
What is JSON validation?
JSON validation checks that your text is valid JSON syntax. The tool shows the exact line and column of any syntax error.