Validate JSON Data
Validate, format, and minify JSON locally in the browser.
What is JSON?
JSON (JavaScript Object Notation) is the standard interchange format for APIs and config files. This tool catches syntax issues, formats readable output, and minifies JSON for production.
Benefits: Instant syntax validation, auto-format with indentation, minify for production, copy-to-clipboard, local browser processing.
Best for: API responses, config files, payload debugging, and production JSON prep.
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Need a different route? Check the next tool in this cluster instead of starting over.
Browse Developer toolsQuestions before you use it
What is the difference between Format and Minify?
Format adds indentation and line breaks so JSON is easier to read. Minify removes whitespace so the payload is smaller and easier to ship in production.
Is there a file size limit?
No artificial limits. Performance depends on your device RAM. Most JSON files process instantly even with tens of thousands of lines.
Why does my JSON fail to validate?
Common issues include trailing commas (not allowed in JSON), single quotes instead of double quotes, missing commas between values, or unescaped special characters in strings.