C# to JSON Converter

Generate sample JSON from C# class definitions with attribute-aware key mapping and nullable type support.

PrettyUse attributesInclude nullscamelCase keysIndent

C# Input

JSON Output

8 properties

{
  "user_id": 0,
  "name": "",
  "email": "",
  "isActive": false,
  "balance": 0,
  "createdAt": "2026-01-01T00:00:00Z",
  "roles": [],
  "age": null
}

How to Use

Paste your C# class code or upload a .cs file.
Configure output options (pretty print, attributes, nulls, casing).
Copy or download the JSON output.

Frequently Asked Questions

How does C# to JSON conversion work?

The tool parses your C# class properties and their types, then generates sample JSON with default values. String becomes "", int becomes 0, bool becomes false, DateTime becomes an ISO string, and List<T> becomes an empty array.

Does it support JSON serialization attributes?

Yes. When "Use attributes" is enabled, [JsonProperty("key")] and [JsonPropertyName("key")] are used as JSON key names.

How are nullable types handled?

Nullable types like int?, bool?, etc. generate null values in the JSON output.

Is my code secure?

Yes. All processing runs in your browser. No code is uploaded to any server.

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