Use our free JSON Formatter and Viewer to format, beautify and validate your JSON data online and ensure your JSON is error-free.





Maintained by Toolsfairy. Thanks to Douglas Crockford of JSON and JS Lint, and Zach Carter, who built a pure JavaScript implementation.

What is JSON?

JSON (JavaScript Object Notation) is a lightweight data-interchange format that is easy for humans to read and write, and easy for machines to parse and generate. It is primarily used to transmit data between a server and web application as text. JSON is based on a subset of JavaScript, but it is a language-independent format.

Example of JSON:

{ "name": "John Doe", "age": 30, "isStudent": false, "courses": ["Math", "Science", "History"], "address": { "street": "123 Main St", "city": "Anytown", "zipcode": "12345" }}

What is validate or well-formed JSON structure?

Validating or ensuring a well-formed JSON structure means checking if the JSON data adheres to the syntax rules of JSON. A well-formed JSON has properly structured elements, such as key-value pairs, arrays, and nested objects, and follows the correct format, such as using double quotes for keys and string values, and properly using commas and colons.

Example of well-formed JSON:

{ "firstName": "Jane", "lastName": "Doe", "age": 25, "isEmployed": true, "skills": ["JavaScript", "HTML", "CSS"]}

Example of malformed JSON:

{ "firstName": "Jane", "lastName": "Doe", "age": 25, "isEmployed": true, "skills": ["JavaScript", "HTML", "CSS",]}

(In the malformed JSON example, the trailing comma after "CSS" makes it invalid.)

What are the data types or Object Types of JSON?

JSON supports the following data types:

  1. String: A sequence of characters enclosed in double quotes.
    "example": "Hello, World!"
  2. Number: Numeric values (integers or floating-point).
    "age": 25
  3. Object: A collection of key-value pairs enclosed in curly braces.
    "address": { "city": "New York", "zipcode": "10001"}
  4. Array: An ordered list of values enclosed in square brackets.
    "skills": ["JavaScript", "HTML", "CSS"]
  5. Boolean: True or false values.
    "isStudent": false
  6. Null: Represents an empty value or no value.
    "middleName": null

How to use JSON View Online tool?

A JSON View Online tool helps format, beautify, and validate your JSON data. Here's how to use it:

  1. Input Your JSON Data: Copy your JSON data and paste it into the input field of the online tool.
  2. Format or Beautify: Click on the "Format" or "Beautify" button to organize the JSON data into a more readable structure, with proper indentation and line breaks.
  3. Validate: Click on the "Validate" button to check if your JSON data is well-formed. The tool will highlight any syntax errors and provide feedback.
  4. View and Edit: Use the viewer to explore the JSON structure. Some tools offer tree view, which allows you to expand and collapse objects and arrays.
  5. Download or Share: After formatting and validating your JSON, you can download the formatted JSON or share it via a link if the tool provides such features.


  1. Paste the following JSON into the tool:
    {"name":"John Doe","age":30,"isStudent":false,"courses":["Math","Science","History"],"address":{"street":"123 Main St","city":"Anytown","zipcode":"12345"}}
  2. Click "Format" or "Beautify" to get:
    { "name": "John Doe", "age": 30, "isStudent": false, "courses": [ "Math", "Science", "History" ], "address": { "street": "123 Main St", "city": "Anytown", "zipcode": "12345" }}
  3. Click "Validate" to ensure there are no syntax errors.
  4. Explore the formatted JSON using the provided viewer options.

Using an online JSON formatter and viewer can significantly improve the readability and accuracy of your JSON data.

JSON Converters