How is this different from the JSON Formatter?

This tool focuses purely on validation feedback with error location; the Formatter also reformats valid JSON with indentation.

Does it catch every kind of JSON error?

Yes — it uses the browser's own JSON parser, the same one your code and API calls rely on.

Yes, there's no hard size limit.

Check JSON for syntax errors, with the exact line and column.

Private by default Instant results No signup

Processed locally

Your JSON never leaves your browser tab.

Precise error location

See the exact line and column of a syntax error.

Instant feedback

No server round-trip needed.

Format, validate and beautify JSON instantly.

Format and indent XML documents.

Beautify messy HTML markup.

Beautify and indent CSS stylesheets.