{ } JSON Workbench0 network requests. Check DevTools

"JSON to C#":{ }

Paste a JSON sample and get clean C# classes. Nested objects become named types, arrays become typed collections, and nullable fields are handled. Powered by quicktype's inference engine running 100% in your browser: zero network requests, so real API payloads stay on your machine.

What is a JSON to C# converter?

Hand-writing classes for an API response is slow and error-prone. This tool infers C# classes from a JSON sample: nested objects become named types, arrays become typed collections, and null/missing values become optional fields. It runs quicktype's inference engine entirely in your browser, so real API payloads (often containing user data or credentials) never leave your machine.

C# mapping notes

  • Properties are PascalCase; original JSON names survive via serializer attributes when enabled.
  • Nullable value types (long?) appear where samples contain null.
  • Compatible with System.Text.Json and Newtonsoft.Json.

How to use

  1. Paste a JSON sample (an API response works well) into the Input pane.
  2. Generated C# classes appear instantly. Nested objects become their own named types.
  3. Non-standard JSON (single quotes, trailing commas, comments) is auto-repaired first.
  4. Copy the code into your project.

Examples

JSON → C# classes

Input
{
  "id": 42,
  "name": "workbench",
  "owner": { "email": "[email protected]", "active": true }
}
Output
public class Root
{
    public long Id { get; set; }
    public string Name { get; set; }
    public Owner Owner { get; set; }
}

FAQ

How do I convert JSON to C# types?

Paste any JSON sample. The classes are inferred from the values and nesting, entirely in your browser. Nothing is uploaded.

How are nested objects handled?

Each distinct nested object becomes its own named type, referenced from the parent, arrays of objects included.

What about optional or null fields?

Fields that are null or missing in parts of the sample are typed as optional/nullable in the generated code.

Can I paste multiple samples?

Paste an array of objects: the type is inferred from the union of all items, which catches optional fields a single sample would miss.

System.Text.Json or Newtonsoft?

The plain classes work with both. Add [JsonPropertyName] or [JsonProperty] attributes if your JSON keys aren't PascalCase-compatible.

Is my JSON uploaded?

No. Generation runs 100% in your browser via quicktype's engine. Check DevTools: zero network requests.

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