Skip to main content
1

JSON Validator

Paste JSON and instantly see if it is valid or invalid. Valid JSON shows a formatted tree view plus size, depth, and key count statistics. Invalid JSON shows the exact error message and position.

More options
Was this tool helpful?
Send output to:
Advertisement

How to use JSON Validator

  1. Paste your JSON into the text area.
  2. Click Validate JSON.
  3. View the formatted tree and stats if valid, or the error location if invalid.

What is JSON Validator?

This tool parses JSON in your browser using the native JSON.parse() API. Valid inputs produce a pretty-printed tree view showing the full structure at a glance. The stats panel reports byte size, maximum nesting depth, and total key count. Invalid inputs surface the parser error message along with a snippet highlighting the character position where parsing failed. No data ever leaves your browser.

Advertisement

FAQ

Is my JSON data sent to a server?
No — all validation runs in your browser using JavaScript. Your data stays private.
What counts as a "key" in the stats?
Every object property name in the entire JSON tree. Nested objects contribute their keys recursively. Arrays do not add to the key count unless they contain objects.
Can I validate very large JSON files?
Yes, the tool works well up to several megabytes. Extremely large files may be slow to tree-format, but validation itself is instant.

Related tools

Author

MW
Marcus Webb"The DevTool Craftsman"

Full-Stack Developer & Tools Architect

Marcus has been writing code since the dial-up era. He's contributed to open-source developer tools and built CI/CD pipelines for startups.

📖 JSON Validator on Wikipedia · Developer Tools on Wikipedia · JSON Validator on Britannica

People also use

← Back to Developer Tools · All tags
Advertisement