100% free tool
JSON Formatter & Validator
Format, minify and validate JSON with clear error messages.
- No sign-up required
- Instant results
- Nothing is uploaded
Formats, minifies and validates JSON. Invalid input gets the parser's own error message, including the character position, which is usually enough to spot the missing comma or bracket. Valid input gets a quick summary of key count and nesting depth.
Frequently asked questions
Common questions about the json formatter & validator.
What happens if my JSON is invalid?+
You get the parser's own error message along with the character position, which is usually enough to find the missing comma, bracket or stray trailing comma.
Can it minify as well as format?+
Yes. Minifying strips every space and newline, which is what you want before putting JSON into a config value or a URL.
Is it safe to paste data with secrets in it?+
The parsing happens in your browser and nothing is sent to a server. That said, treat any tool with real credentials carefully - redact them first if you can.
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