JSON to C# Class Generator

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What Is JSON to C# Conversion?

JSON to C# conversion automatically generates strongly-typed C# classes from a JSON document. Instead of manually writing model classes to deserialize API responses, you can paste the JSON and get ready-to-use C# code with proper property types, naming conventions, and serialization attributes.

This is especially valuable in .NET development where strongly-typed models are preferred over dynamic JSON parsing for IntelliSense support, compile-time checking, and maintainability.

How Does the Conversion Work?

The converter analyzes the JSON structure and infers C# types:

• JSON strings → string
• JSON numbers (integer) → int or long
• JSON numbers (decimal) → double or decimal
• JSON booleans → bool
• JSON null → object? (nullable)
• JSON objects → Nested C# classes
• JSON arrays → List<T> where T is inferred from array elements

Common Use Cases

• API Integration: Generate C# models from REST API response samples for use with HttpClient and System.Text.Json.
• Configuration Models: Create typed configuration classes from appsettings.json structures for the Options pattern.
• Data Import: Generate models for deserializing JSON data files in ETL or data migration projects.
• Rapid Prototyping: Quickly scaffold model classes during development instead of writing them manually.
• Code Generation: Use as part of a build pipeline to keep C# models in sync with evolving JSON APIs.

Frequently Asked Questions

Does the generator handle nested objects?

Yes. Nested JSON objects are converted to separate C# classes with appropriate property references. Deeply nested structures produce multiple classes, each representing a level of the hierarchy.

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

System.Text.Json is the built-in, high-performance option recommended for new .NET projects. Newtonsoft.Json (Json.NET) offers more features and flexibility but requires an additional NuGet package. The generated classes work with both serializers.