JSON Formatter & Validator Online Free
Format, validate, and minify JSON instantly in your browser. Paste your JSON and get clean, readable output with syntax error detection.
How to Format and Validate JSON
- 1
Paste your JSON
Paste or type your JSON into the input box on the left. The tool accepts any valid or invalid JSON string.
- 2
Format, minify, or validate
Click "Format" to pretty-print with indentation, "Minify" to compact it, or "Validate" to check for syntax errors without changing the output.
- 3
Copy the result
The result appears in the output box on the right. Click "Copy" to copy it to your clipboard.
JSON (JavaScript Object Notation) is the universal data interchange format used by virtually every web API, configuration file, and data pipeline. Poorly formatted JSON is hard to read and debug; this tool makes it readable in one click.
Format vs Minify: Formatted JSON is indented with 2 spaces per level, making nested structures easy to scan. Minified JSON strips all whitespace, cutting payload size for API requests or storage. Both operations validate the JSON as part of the process.
Common JSON errors: Trailing commas (the last item in an object or array must not have a comma), single-quoted strings (JSON requires double quotes), unquoted keys, and undefined values. The validator error message includes the character position to help you locate the issue quickly.