What is JSON Formatter & Validator Online?
JSON (JavaScript Object Notation) is the universal data interchange format of the web. Raw JSON from APIs is often minified — no whitespace, compact — making it unreadable for humans. This formatter prettifies it with proper indentation, syntax highlighting, and immediate validation so you can spot errors at a glance.
How to Use JSON Formatter & Validator Online
- Paste your raw JSON into the input area.
- The formatter validates and prettifies it instantly.
- If invalid, the error message pinpoints the exact position of the syntax error.
- Use the Minify button to compact JSON for transmission.
Example
Prettified JSON output
Input
{"name":"John","age":30}Output
{
"name": "John",
"age": 30
}Frequently Asked Questions
Why is my JSON invalid?
Common JSON errors: trailing commas (not allowed in JSON), single quotes (must use double), unquoted keys, and undefined/NaN values (not valid JSON types).
What is the difference between JSON and YAML?
JSON is strict, machine-friendly, and widely supported. YAML is more human-readable, supports comments, and is commonly used for configuration files.