JSON to C Converter

Use JSON to C Converter, review the result, and keep the original until the output is checked.

Input JSON
JSON Input
Generated C Struct
C Output
Enter JSON and click "Convert to C" to see generated C struct code...
100% browser-side processing — your data is never uploaded to any server. · Per-tool input limit: 1 MB
100% browser-based No upload to server Free to use

Frequently Asked Questions About JSON to C Converter

Can it fix JSON with trailing commas or comments?

Yes. The repair step removes trailing commas, comments and a byte-order mark, turns single-quoted strings into double-quoted ones and quotes bare member names, then re-reads the document. Values it cannot infer, such as a Python True or a missing closing brace, still need a manual edit.

Why do large numbers change when I format JSON?

JavaScript numbers are IEEE-754 doubles, so most parsers rewrite an integer above 2^53 and lose its tail digits. This page keeps those long literals exactly as you typed them, but a parser elsewhere in your stack will not, so keep such ids as strings in the source document.

Does the generated code include a JSON parser?

Only where the page offers a parser option; otherwise you get type declarations to pair with the parser you already use.

Why are arrays generated with a count field?

C arrays carry no length, so the struct records one explicitly to keep the data usable.

What is JSON?

JSON (JavaScript Object Notation) is a lightweight data-interchange format. It uses objects {}, arrays [], strings, numbers, booleans, and null.

Why format JSON?

API responses and config files are often minified. The JSON to C Converter expands them with indentation so you can spot nested keys, validate structure, and debug faster.