Developer Tool
🧩 JSON Formatter & Validator
Paste JSON to format (beautify), minify, and validate. See line numbers, character count, and copy the result instantly. All processing is local.
🧠 How JSON Formatting Works
- Parse: The tool reads your JSON string and converts it into a JavaScript object.
- Format (Beautify): The object is re-serialized with 2-space indentation, adding line breaks for readability.
- Minify: The object is re-serialized without any extra whitespace — smallest possible size.
- Validate: The parser checks syntax. If there's an error, it reports the line and column number.
- Stats: Line count, character count, and byte size are updated live as you type.
Tip: Use the Sample button to load a demo JSON object and see the formatter in action.
❓ Frequently Asked Questions
What is a JSON formatter?
A JSON formatter (or beautifier) takes minified or messy JSON and adds indentation and line breaks to make it human-readable. It also validates the JSON syntax.
How do I validate JSON?
Paste your JSON into the input box and click Validate. The tool will parse it and either confirm it is valid or show you the exact line and column where the error occurred.
What does minifying JSON do?
Minifying removes all unnecessary whitespace, line breaks, and indentation to produce the smallest possible JSON string. This is useful for reducing payload size in APIs and web apps.
Is my JSON data sent to a server?
No. Everything is processed locally in your browser using JavaScript. Your JSON never leaves your device.
Can I format large JSON files?
Yes, but extremely large files (several megabytes) may be slow depending on your device. For everyday API responses and config files, it handles them instantly.
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