JSON to C# Class Generator Online — Free C# Model Generator

How to JSON to C# Class Online

1. 1

   Paste valid JSON into the input area on the left.

2. 2

   Set the root class name (defaults to 'Root') using the option field.

3. 3

   Choose the serializer: System.Text.Json or Newtonsoft.Json (Json.NET).

4. 4

   Toggle record types (C# 9+) and nullable reference types to match your project settings.

5. 5

   Click Convert or press ⌘↵ (Mac) / Ctrl+Enter (Windows) to generate C# classes.

6. 6

   Copy the generated C# code or download it as a .cs file.

JSON to C# Class Features

• ✓

  Generates C# classes or records from any JSON object or array.

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  Supports nested objects — creates separate named classes for each nested structure.

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  System.Text.Json mode: uses [JsonPropertyName] attributes.

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  Newtonsoft.Json mode: uses [JsonProperty] attributes.

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  Optional record types (record class) for immutable C# 9+ data models.

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  Optional nullable reference type annotations (string?, int?, etc.).

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  Smart type inference: string, int, double, bool, List<T>, and nullable variants.

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  Works entirely in your browser — JSON never leaves your device.

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  Keyboard shortcut ⌘↵ for instant conversion.

Frequently Asked Questions

What is JSON to C# class conversion?

JSON to C# generates C# class definitions from a JSON sample, complete with serialization attributes. Instead of writing model classes by hand, paste your API response and get strongly-typed C# code ready for use with System.Text.Json or Newtonsoft.Json.

Should I use System.Text.Json or Newtonsoft.Json?

System.Text.Json is the built-in .NET serializer (no extra packages) and is preferred for new .NET 6+ projects. Newtonsoft.Json (Json.NET) is the classic library with more features and is still widely used in existing codebases. Choose whichever your project already uses.

What are C# record types?

Records (introduced in C# 9) are reference types with built-in value equality, immutability via init-only properties, and a concise syntax. They are ideal for modelling API response payloads that should not be mutated after deserialization.

Is my JSON data safe?

All conversion runs in your browser using pure JavaScript. No JSON is ever sent to a server. Your data stays completely private.

Can it handle nested JSON?

Yes. Each nested JSON object becomes its own C# class. The parent class references the child class by name, and all classes are output together in the same file.

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