📦 What is this JSON Formatter?

The JSON Formatter tool helps you quickly format, validate, and beautify JSON data. It ensures your JSON is human-readable and properly indented, making it easier to debug or share. Built with Spring Boot and Thymeleaf, it’s optimized for developers who work with REST APIs, configuration files, or data exchange.

JSON (JavaScript Object Notation) is a lightweight data format widely used for exchanging data between client and server applications. Properly formatted JSON improves readability and reduces errors.

🚀 How to Use

Paste your JSON code into the text area, then click Format to instantly beautify it with indentation. You can also minify JSON to remove unnecessary spaces for faster transmission.

Example: Paste {"id":1,"name":"Alice","skills":["Java","Spring","Regex"]} and format it to see a neatly indented structure.

💡 Why Use This Tool?

While IDEs like IntelliJ or VS Code offer JSON formatting, having a quick web-based tool makes it easier when you’re working outside your development environment or reviewing API responses.

This formatter also validates JSON syntax, which helps catch missing commas, braces, or incorrect nesting before deploying to production.

📘 JSON Basics

Data is represented as key: value pairs
Keys must be wrapped in double quotes (" ")
Values can be strings, numbers, objects, arrays, true, false, or null
Objects are wrapped in { }, arrays in [ ]

Example of valid JSON:

{
  "user": {
    "id": 42,
    "active": true,
    "roles": ["admin", "editor"]
  }
}

🧩 Java Example


import com.fasterxml.jackson.databind.*;

public class JsonFormatExample {
    public static void main(String[] args) throws Exception {
        String raw = "{\"id\":1,\"name\":\"Alice\"}";
        ObjectMapper mapper = new ObjectMapper();

        // Parse JSON string into a tree
        JsonNode node = mapper.readTree(raw);

        // Pretty print with indentation
        String formatted = mapper.writerWithDefaultPrettyPrinter()
                                 .writeValueAsString(node);

        System.out.println(formatted);
    }
}

Using Jackson in Java, you can parse and format JSON easily. The formatter below helps you validate and clean your JSON before using it in your applications.

🔍 JSON Validation

The tool checks whether your JSON is valid before formatting. If your input has syntax errors (like missing commas, extra brackets, or unquoted keys), you’ll get an error message.

This helps ensure that your data can be safely parsed by applications or APIs.

📉 Minify JSON

Minification removes whitespace, tabs, and line breaks from JSON. This is useful for reducing payload size in APIs or web apps, leading to faster network transfer.

Example: {"id":1,"name":"Alice"} instead of formatted multiline JSON.

🌐 JSON vs XML

JSON is often preferred over XML because it is simpler, more compact, and integrates naturally with JavaScript.

✅ Easier to read/write
✅ Less verbose
✅ Native support in browsers and APIs

XML still has advantages for document-based structures, but JSON dominates modern APIs.

🛡️ Security Considerations

Always validate and sanitize JSON from untrusted sources. Malformed or malicious JSON can lead to parsing errors or even injection attacks if not handled properly.

Never rely solely on client-side validation — server-side checks are essential.

🧩 JSON Formatter