Free online JSON validator
JSON Validator
Validate JSON syntax, inspect parse errors, and view a clean formatted preview.
Developer Tools
Browser based
Runs on the current page
Copy-ready
Use the output where you work
No sign-in
Open the tool and get moving
Developer tool
Validate JSON
Check whether pasted JSON parses cleanly and copy a formatted preview when it is valid.
Built for the task
Format, validate, encode, decode, and test.
Fast browser utilities for common implementation, debugging, and content-cleanup tasks.
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FAQ
JSON Validator questions.
What makes JSON invalid?
Common issues include trailing commas, single-quoted strings, unquoted keys, comments, and missing braces or brackets.
Can this validator fix invalid JSON automatically?
It reports the syntax issue and formats valid JSON, but it does not guess changes that could alter the data.
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