What is JSON validation?

JSON validation is the process of checking if your JSON code follows the official syntax rules defined by RFC 8259. It ensures data integrity before processing.

How do I fix trailing commas in JSON?

Our tool automatically removes trailing commas from arrays and objects when you click the 'Fix JSON' button, making your code valid instantly.

Can I convert single quotes to double quotes?

Yes. Standard JSON requires double quotes. Our auto-fix engine detects single-quoted keys and strings and converts them to valid double quotes.

Absolutely. JSON Parser Pro runs entirely in your browser. No data is sent to any server, ensuring 100% privacy and security.

What is the difference between Minify and Format?

Format (Prettify) adds whitespace and indentation to make JSON readable for humans. Minify removes all unnecessary whitespace to reduce file size for computers.

JSON Parser Pro - The Ultimate IDE-Grade Editor

What is JSON and why validate it?

JSON (JavaScript Object Notation) is the backbone of modern web data. It's a lightweight format used for storing and transporting data between servers and web pages. However, JSON is notoriously unforgiving. A single misplaced comma or a missing quote can crash an entire application.

Validation is the critical step of ensuring your JSON string conforms to the strict syntax rules defined by RFC 8259. Our tool acts as your first line of defense, catching syntax errors before they hit production.

// Valid JSON Example

{

"name": "Project Alpha",

"status": "Active",

"count": 42

}

Common JSON Errors We Fix

Even experienced developers make mistakes. Our "Smart Fix" engine is designed to handle the most common frustrations automatically:

Trailing Commas

JSON does not allow a comma after the last element in an array or object.

{"a": 1,}

Single Quotes

JSON requires double quotes for keys and string values. Single quotes are invalid.

{'key': 'value'}

Unquoted Keys

Unlike JavaScript objects, JSON keys must always be enclosed in double quotes.

{key: "value"}

How to Use This Tool

Paste Your Data

Simply copy your JSON code and paste it into the left editor panel. The tool will immediately start analyzing the syntax.

Check the Status

Look at the status indicator in the toolbar. Green means valid, red means there's an error. If there's an error, a red bar will appear at the bottom detailing the exact line number.

Format or Fix

Use the Format button to beautify messy code. If errors are found, click Fix JSON to let our engine attempt an automatic repair.

Frequently Asked Questions

Is my JSON data sent to your server?

No. This tool is a client-side application. All processing happens right here in your browser's memory using JavaScript. Your sensitive data never leaves your device.

Why is my valid JavaScript object showing as invalid JSON?

JavaScript objects and JSON are similar but not identical. JSON requires all keys to be double-quoted (e.g., "key": "value"), whereas JavaScript allows unquoted keys (key: "value"). Our tool can fix this for you automatically.

Does this tool support comments in JSON?

Standard JSON (RFC 8259) does not support comments. However, some parsers (like JSON5) do. This validator strictly adheres to the standard to ensure maximum compatibility with all systems.

How large of a file can I paste?

Since we use your browser's engine, performance depends on your device. However, we have optimized the rendering to handle files up to 5MB smoothly, which covers 99% of use cases.