JSON Formatter
Beautify and format JSON with syntax highlighting
About JSON Formatter
How JSON Formatter Works
Paste raw JSON and the engine parses it locally compliant with IETF RFC 8259 and ECMA-404, applying 2-space or 4-space indentation and syntax highlighting. With 0 HTTP requests transmitted and 0 bytes leaving the browser, your configuration files and API responses stay 100% private in memory.
The JSON Formatter takes raw, minified, or messy JSON and returns it as clean, human-readable text with consistent indentation and syntax highlighting. It is the fastest way to make an API response, configuration file, or log entry legible. A typical use case is pasting a compact API payload returned by a backend service into the tool to understand its structure before writing client code. Because everything runs in your browser, the data you paste never leaves your machine, which keeps secrets and tokens safe. Developers use it daily to debug endpoints, review webhook payloads, and clean up configuration stored in version control. The formatter also normalizes spacing and line breaks so files are easier to review in pull requests and diffs.
Frequently asked questions
Does it send my JSON to a server?+
No. All parsing happens locally in your browser, so your data stays private.
Can it handle large files?+
Yes for typical payloads. Extremely large files may be slower, but nothing is uploaded.
Will it fix invalid JSON?+
It formats valid JSON. Invalid syntax is best caught first with a validator.
Limitations
It does not repair malformed JSON or resolve external references and schemas. Very deeply nested structures can be harder to scan visually.