JSON Validator
Paste or upload JSON to check it for syntax errors. Valid JSON is confirmed; invalid JSON is flagged with the precise line and column of the problem.
Input JSON
LocalResult
—About JSON Validator
The JSON Validator checks whether a string is well-formed JSON and, when it is not, tells you exactly where it breaks. It is for anyone integrating an API or editing config who needs a fast yes/no answer plus an actionable error location.
A misplaced comma can break an entire integration. Validating locally gives you the failure point immediately, without exposing the payload to an external validator.
Step by step
- Paste or upload the JSON you want to check.
- The validator parses it and reports either a success state or a specific error.
- On failure, note the line and column it reports and jump to that spot in your source.
- Fix the issue and re-check until the input validates cleanly.
What it offers
- Syntax error detection
- Clear valid confirmation
- Error position hints
- Paste or upload input
Tips for best results
- Validate API responses during development to catch contract changes early.
- Remember that valid JSON still may not match your schema — validation here is syntactic, not semantic.
- Watch for smart quotes pasted from documents; they are a common cause of “unexpected token” errors.
Why people use it
Clear verdict
An unambiguous valid / invalid result with no guesswork.
Located errors
Points to the line and column of the first parse failure.
No upload
The content never leaves your browser.
Free and instant
Check as many payloads as you like with no limits.
Common questions
This runs entirely in your browser
No file or text you enter here is uploaded. Encoding and decoding happen on your device using native browser APIs — close the tab and nothing remains on a server.