JSON Formatter & Validator

Format, validate, and beautify JSON data with syntax highlighting.

What is JSON Formatter & Validator?

JSON (JavaScript Object Notation) is the most widely used data format for APIs and web applications. Minified JSON is difficult to read and debug. This tool formats, validates, and beautifies JSON data with proper indentation and syntax highlighting, making it easy to understand complex data structures and find errors in your JSON.

How to use this tool

  1. Paste your JSON data in the input field
  2. Click Process to format and validate
  3. View the beautified output with proper indentation
  4. Syntax errors will be highlighted with their location

Frequently asked questions

What is valid JSON?
Valid JSON must follow strict syntax rules: strings must use double quotes (not single quotes), no trailing commas are allowed, property names must be quoted, and values can be strings, numbers, booleans, null, arrays, or objects. Common errors include using single quotes, trailing commas, and unquoted property names.
What is the difference between JSON and JavaScript objects?
While JSON syntax is based on JavaScript object notation, they have key differences. JSON requires double-quoted property names and strings, does not support functions, undefined, or comments, and is always a string format meant for data exchange. JavaScript objects are in-memory data structures with more flexibility.
How large can a JSON file be?
There is no official size limit for JSON, but practical limits depend on the parser and available memory. Most web APIs handle payloads up to 10-50 MB. For larger datasets, consider streaming JSON parsers, pagination, or alternative formats like Protocol Buffers or MessagePack.

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