JSON to C#

Generate C# classes or records from JSON.

JSON to C# – Generate C# classes or records from JSON

The JSON to C# converter reads a sample JSON document and generates C# classes or records. Paste an API response or a config object, adjust the options, and copy ready-to-use code. The whole conversion runs in your browser, so your data never leaves the page.

How it works

The tool infers a type for every value: strings, integers, floating-point numbers, booleans, null, nested objects and arrays. Repeated objects in an array are merged, so a field that is missing from some items becomes optional, and objects with the same shape reuse a single generated type. The result includes System.Text.Json or Newtonsoft.Json attributes, nullable types and List<T> or arrays.

Why generate from JSON?

When you integrate with an API you usually have example responses before you have formal types. Writing matching models by hand is slow and error-prone for large payloads. Generating them takes a second and gives you a consistent, correct starting point that you can refine — rename a type, fix an ambiguous number, or mark a field required.

Tips for the best result

  • Paste a representative sample. The more complete the example, the more accurate the inferred types; include optional fields where you can.
  • For an array of objects, the tool merges all items, so pass several rows rather than just one.
  • Dates and IDs are only strings in JSON, so review timestamp and identifier fields after generating.
  • Use the generated code as a solid draft and adapt field types or names to your domain.

Validate your input first with the JSON Validator, format it with the JSON Formatter, or generate a different language from the same data using the other JSON to code converters.

Frequently Asked Questions

No. Parsing and code generation run entirely in your browser with JavaScript. You can use the converter offline once the page has loaded, which is useful for sensitive payloads.

When you paste an array of objects, the tool merges them: a key that appears in only some items is marked optional (and nullable where a value is null). A single object treats every key as present.

There is no type information in an empty array or a bare null, so the tool falls back to the most permissive type for that language (for example any, interface{} or object). Replace the sample value with a real one for a precise type.

Yes. Set the root type name and the other options above, then edit the output freely. The generated code is meant as an accurate starting point, not a locked result.