JSON Formatter & Validator

This free JSON formatter beautifies messy JSON into readable, indented output, minifies it for compact transport, and validates it with precise error messages that point to the exact line and column where parsing failed. It works entirely in your browser — your data is never uploaded, stored or sent anywhere, so it is safe for API responses containing private or production data.

Common uses: pretty-printing API responses, debugging configuration files (package.json, tsconfig.json, webhook payloads), checking whether a JSON document is valid before committing it, and reducing payload size before sending data over the wire. The validator uses the same JSON parser as the browser itself, so if it passes here, it conforms to the JSON standard as implemented in every modern runtime.