Why does my JSON with comments fail?

The JSON specification has no comment syntax. Formats that allow them (JSONC, JSON5) are supersets. Strip the comments first, or use a YAML tool, which does support them.

Does formatting change my data?

Only whitespace, unless you enable key sorting. Very large integers are the one exception: JavaScript numbers cannot represent every 64-bit integer exactly.

JSON Formatter

Reindent minified or malformed JSON into something readable.

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About this tool

Parses the document with the browser's own JSON parser, then re-serialises it at your chosen indentation. Because it round-trips through a real parse, anything that comes out the other side is guaranteed to be valid JSON.

Limitations

Comments and trailing commas are not valid JSON and will be reported as errors.
Key order is preserved except where duplicate keys exist — the last value wins, as in any JSON parser.
Numbers larger than 2^53 lose precision because they pass through JavaScript numbers.

Questions

Why does my JSON with comments fail?: The JSON specification has no comment syntax. Formats that allow them (JSONC, JSON5) are supersets. Strip the comments first, or use a YAML tool, which does support them.
Does formatting change my data?: Only whitespace, unless you enable key sorting. Very large integers are the one exception: JavaScript numbers cannot represent every 64-bit integer exactly.

Privacy

This page does its work in your browser. What you paste is processed by JavaScript running on your own device and is never sent to a DevToolery server — there is no server that could receive it. The page itself is a static file delivered by a CDN. See exactly what is stored.