JSON Formatter & Validator

Enter JSON

Output

Enter JSON to validate or format

About JSON Formatting and Validation

JSON (JavaScript Object Notation) is a lightweight data-interchange format that is easy to read and write for humans and machines. It is commonly used to exchange data between a server and a client or between different systems.

When working with JSON, formatting and validation are essential to ensure the data is syntactically correct and easy to read. Properly formatted JSON enhances readability, while validation ensures the JSON structure adheres to standard rules.

Why Use JSON Formatter and Validator?

Improve Readability: Make compact JSON easier to understand by applying consistent indentation and line breaks.
Debug Faster: Instantly identify syntax errors and invalid JSON structures during development.
Save Time: Simplifies working with JSON for developers, students, and data analysts.
Standard Compliance: Ensure your JSON adheres to the correct syntax before using it in your application.

Using JSON in JavaScript

If you're working with JSON in JavaScript, you can use the built-in JSON object for parsing, validating, and stringifying JSON data.

Formatting JSON with `JSON.stringify()`

The JSON.stringify() method converts a JavaScript object into a JSON string. You can also add formatting (pretty-printing) using its optional arguments. Example:

const data = {
  name: "John Doe",
  age: 30,
  skills: ["JavaScript", "HTML", "CSS"]
};

const formattedJSON = JSON.stringify(data, null, 2); // Pretty-print with 2-space indentation
console.log(formattedJSON);

/* Output:
{
  "name": "John Doe",
  "age": 30,
  "skills": [
    "JavaScript",
    "HTML",
    "CSS"
  ]
}
*/

Validating JSON with `JSON.parse()`

The JSON.parse() method parses a JSON string and converts it into a JavaScript object. If the JSON string is invalid, it throws an error, making it a useful tool for validation. Example:

const jsonString = '{"name": "Jane Doe", "age": 25}';

try {
  const parsedData = JSON.parse(jsonString); // Valid JSON
  console.log(parsedData);
  // Output: { name: 'Jane Doe', age: 25 }
} catch (error) {
  console.error("Invalid JSON:", error.message);
}

Catching Invalid JSON

If the JSON string contains errors (e.g., missing quotes, extra commas) JSON.parse() will throw an error. Example:

const invalidJSONString = '{"name": "John", "age": 30,'; // Invalid JSON (trailing comma)

try {
  const parsedData = JSON.parse(invalidJSONString);
  console.log(parsedData);
} catch (error) {
  console.error("Error:", error.message);
  // Output: Error: Unexpected end of JSON input
}