Json2POJOJson2POJO
RFC 8259 Compliant

JSON Validator & Debugger

Paste your JSON below to find syntax errors instantly. We pinpoint the exact line and character causing the issue.

JSON Input

Validation Status

waiting for input...

How to Validate JSON

Validation ensures your data structure follows the strict rules of RFC 8259. Unlike JavaScript Objects, JSON is invalid if it has:

  • Trailing Commas
  • Single Quotes
  • Comments

Debugging Common Errors

Error: Unexpected token '}' at position 45

Stop Guessing. Start Fixing.

Most validators just say "Invalid JSON" and crash. We don't. We pinpoint the exact line, character, and context of the error so you can fix it in seconds.

Formatted Output

Auto-Formatting

Once valid, use the "Format" button to beautify minified JSON, making it readable for humans.

Next Steps

Valid JSON? Convert it to Java.

Stop writing boilerplate. Generate fully annotated Java classes instantly.

Jackson GuideGson Guide

Validate JSON in Code

Need to validate JSON programmatically? Here are snippets for popular languages:

JavaScript

function isValidJSON(str) {
  try {
    JSON.parse(str);
    return true;
  } catch (e) {
    console.error(e.message);
    return false;
  }
}

Java (Jackson)

ObjectMapper mapper = new ObjectMapper();
try {
  mapper.readTree(jsonString);
  return true;
} catch (JsonProcessingException e) {
  System.out.println(e.getMessage());
  return false;
}

Validation FAQ

Is this tool secure?

Yes. All validation happens Client-Side in your browser. Your data is never sent to our servers.

Can I use single quotes?

No. JSON strictly requires double quotes (`"key": "value"`). If you came from JavaScript, this is a common mistake.

Can I validate against a Schema?

This tool validates syntax (e.g., missing commas). evaluating against a JSON Schema (structure/types) requires a dedicated Schema Validator. Check out our JSON Schema Guide.

JSON vs JS Object?

They look similar but are different. JSON is a String transport format. JS Objects are Variables.
JSON: {"key": "val"}
JS: {key: 'val'} (No quotes needed on keys)