Live
JSON Formatter
Pretty-print or minify the same JSON with one click.
Web · Free tool
JSON Validator
Paste JSON and get an instant verdict — valid, or invalid with the exact line : column and a look at the offending line.
Validate JSON
Validation runs live as you type — nothing leaves your device.
Verdict
Paste JSON to start.
Around the error
How it works
How the JSON validator works
Typing = validating
Every keystroke re-runs a strict JSON parse. The moment something breaks, the tool shows the first error's line and column instead of a cryptic message.
See the offending line
Below the error, the validator shows the exact line near the failure so you can spot the missing comma, stray quote, or unclosed brace at a glance.
Fix one thing, not ten
JSON parsers rarely chain errors — repair the single reported location and the document usually parses cleanly.
Questions
JSON validator FAQ
How is this different from the JSON formatter?
The JSON Validator focuses on correctness: it tells you whether the document parses and pinpoints the exact syntax error with its line and column. The JSON Formatter does that too, but its focus is pretty-printing and minifying the output.
Why does a tiny mistake produce a big error message?
JSON parsers report the character where they can no longer continue. A missing comma or unescaped quote shifts everything after it, so most errors share one root cause — fix that spot and the document parses.
Can I paste a whole config file?
Yes. The validator handles large files comfortably, validates live as you type, and only ever runs locally on your machine.