Add valid JSON
Paste an object or array, or open a local .json file. Nested structures and representative array records produce the best types.
Intelligent JSON type inference
JSON to C# Converter
Generate clean C# model classes from real JSON data. Infer nested objects, generic Lists, numeric types, nullable properties, and safe names for System.Text.Json.
- Nested C# model inference
- Private browser processing
- Copy or download C#
JSON input
Generated C#0 bytes
How to convert JSON to C#
Generate reusable C# classes in three focused steps.
Configure the model
Name the root class, choose nullable reference output, and let the converter infer nested property types.
Export C#
Review the generated source, copy it into your project, or download a ready-to-use .cs file.
Type inference designed for real API data
The generator examines complete structures rather than guessing from the first property alone.
Nested models
Objects inside objects receive clear named definitions instead of unreadable inline blocks.
Generic collections
JSON arrays become typed C# Lists, including collections of generated nested model classes.
JSON mappings
Original keys are preserved with System.Text.Json JsonPropertyName attributes when required.
Private conversion
JSON parsing and type generation happen locally in your browser without a server upload.
How JSON becomes a C# model
Strings become string, whole numbers become long, decimal numbers become double, booleans become bool, arrays become typed List<T> properties, and objects become named classes.
Safe deserialization names
JSON keys may contain hyphens, spaces, C# keywords, or leading numbers. The generator creates a valid PascalCase property and adds [JsonPropertyName] for accurate System.Text.Json mapping.
Use representative JSON
Generated classes describe the supplied sample. Include realistic array records and null values so the inferred property types match your API.
// JSON { "id": 42, "name": "Alex", "roles": ["admin", "editor"] } // C# public class Root { public long Id { get; set; } public string Name { get; set; } public List<string> Roles { get; set; } }
JSON to C# converter FAQs
Practical details about inference, arrays, nulls, and generated definitions.
Does the converter support nested JSON?
Yes. Nested objects become named C# classes, and arrays of objects become typed Lists of generated classes.
How are arrays of objects handled?
Object samples are merged so the generated element class includes fields found across the supplied records.
What happens to null values?
Known types become nullable, such as long? or string?. A value that is only null becomes object? because its concrete type cannot be inferred.
Does it use nullable reference types?
Yes, when enabled. Nullable strings, objects, and collections receive the ? annotation for modern C# projects.
Are invalid JSON property names supported?
Yes. The generator creates a safe C# property and adds a JsonPropertyName attribute containing the original key.
What type is generated for an empty array?
An empty array provides no element evidence, so the property is generated as List<object>.
Is my JSON uploaded to the server?
No. Parsing, inference, copying, and downloading happen locally inside your browser.
Should generated types be reviewed?
Yes. The definitions describe the supplied sample. Compare them with your API contract, especially when optional or rare fields may be absent.