JSON Formatter & Validator

Prettify, validate, format, and minify JSON data objects in real time.

JSON Input

Output Result

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Understanding JSON Formatting, Indentation, and Payload Validation

JavaScript Object Notation (JSON) is a lightweight, text-based data format used to transmit structured data between servers and web applications. Formatting and validating JSON payloads is essential for debugging APIs and checking data integrity.

The Syntax Rules of Valid JSON

JSON requires strict formatting rules:

  • Keys and string values must be enclosed in double quotes (not single quotes).
  • Trailing commas at the end of objects or arrays are not allowed.
  • Data must be structured as key-value pairs, arrays, strings, numbers, booleans, or null.
Our validator parses inputs to check for syntax issues (like missing brackets or illegal characters) and displays clear errors if validation fails.

Contextual Developer Tools

If you are converting data structures between JSON and XML configurations, check out our XML Formatter. If you are validating customer sign-up email payloads, visit our Email Validator.

Frequently Asked Questions

Why are trailing commas invalid in JSON?
The JSON standard is designed for simple, strict parsing. Trailing commas can cause errors in certain parsers and are explicitly prohibited.
What is the difference between JSON and XML?
JSON is lightweight, matches JavaScript objects natively, and is easy to read. XML is markup-based, verbose, and supports complex schemas and document validation.