Online JSON Validator & Formatter

Instantly validate, format, and beautify your JSON data with our simple and powerful online tool.

Your Ultimate Online JSON Checker and Beautifier

Whether you are a developer working with APIs, a data scientist handling complex datasets, or just someone learning to code, dealing with JSON (JavaScript Object Notation) is a daily task. A single misplaced comma or bracket can break your application. Our free online JSON validator is designed to be your first line of defense, helping you find and fix syntax errors in seconds.

What is JSON?

JSON, or JavaScript Object Notation, is a lightweight, text-based data-interchange format. It is easy for humans to read and write and easy for machines to parse and generate. Because of its simplicity and flexibility, JSON has become the de-facto standard for transmitting data between a server and a web application, often replacing older formats like XML. It is built on two structures: a collection of name/value pairs (an object) and an ordered list of values (an array).

Why is a JSON Validator Essential?

Validating your JSON data before using it in an application is a critical step. Here’s why our JSON checker is an indispensable tool:

• Catch Syntax Errors Instantly: Our tool immediately highlights errors like missing commas, trailing commas, incorrect quote types, or mismatched brackets.
• Save Debugging Time: Instead of spending hours trying to figure out why your application is crashing, a quick validation can point you to the exact source of the problem.
• Ensure Data Integrity: Validating ensures that the structure of your data is correct before it's processed, preventing unexpected behavior or data corruption.
• Learn JSON Structure: By seeing the errors and using the beautifier, beginners can quickly learn the correct syntax and formatting rules for writing valid JSON.

How to Use Our JSON Validator and Formatter

1. Paste Your Code: Copy your JSON data and paste it into the text area above.
2. Validate: Click the "Validate JSON" button. The tool will immediately tell you if your JSON is valid or not. If it's invalid, it will provide a descriptive error message.
3. Format/Beautify: If your JSON is valid but poorly formatted, click the "Format / Beautify" button. The tool will automatically indent your code, making it clean and readable.
4. Clear: Click the "Clear" button to easily start over with a fresh input field.

Common JSON Errors to Avoid

• Trailing Commas: Placing a comma after the last element in an object or array is a common mistake (e.g., {"key": "value",}).
• Using Single Quotes: JSON keys and string values must be enclosed in double quotes ("). Single quotes (') are not allowed.
• Missing Commas: Forgetting to place a comma between elements in an object or array.
• Unclosed Brackets or Braces: Every opening { or [ must have a corresponding closing } or ].

Bookmark this page for quick and easy access to a reliable JSON validator and formatter whenever you need it.