JSON to Code Converter

What is JSON to Code Converter?

JSON to Code is a free in-browser type generator that reads a JSON sample and writes the matching data model in your chosen language. Pick a target from the Convert to menu - TypeScript interface, Go struct, Rust serde struct, Zod schema, or JSON Schema - and set a Root type name to label the top-level type. The inference engine walks the JSON: strings, numbers, booleans, and null map to native types, nested objects are lifted into their own named types, arrays adopt their element type, and keys missing from some array elements become optional. Frontend and backend developers use it to scaffold DTOs from API responses, draft validation schemas, and keep client and server types in sync without hand-writing boilerplate.

How to use JSON to Code Converter

1. Paste or type a representative JSON sample into the input box, or click Sample to load an example.
2. Open Settings and pick a target under Convert to: TypeScript, Go, Rust, Zod, or JSON Schema.
3. Set the Root type name to control the name of the top-level interface, struct, or schema.
4. Read the generated code in the output panel - it refreshes automatically as you edit the JSON or change options.
5. Check the Types stat to see how many named types were inferred, then click Copy to grab the result.

Examples

{ "id": 1, "name": "Ada", "active": true }

export interface Root {
  id: number;
  name: string;
  active: boolean;
}

{ "user": { "age": 30 } }

type User struct {
	Age float64 `json:"age"`
}

type Root struct {
	User User `json:"user"`
}

Frequently asked questions

Is my JSON uploaded anywhere?

No. Parsing and code generation run entirely in your browser using a built-in inference engine. Your JSON never leaves your device, and the tool keeps working offline.

Which targets are supported?

TypeScript interfaces, Go structs (with json tags and omitempty for optional fields), Rust serde structs (with Serialize/Deserialize derives and rename when a field is renamed), Zod schemas, and draft-07 JSON Schema. The tool only generates what it can infer faithfully from your sample.

How are optional fields decided?

From your sample. When an array contains objects and a key is missing from some of them, that key is inferred as optional. Other than that, every key present in the sample is treated as required.

What about numbers, nulls, and mixed types?

Numbers map to the language's float type (number, float64, f64), null maps to a nullable or value type per target, and a field that holds different types across samples falls back to a permissive type (unknown, interface{}, serde_json::Value) rather than guessing.

Why is my output empty or showing an error?

The input must be valid JSON. If parsing fails, the tool shows the error with a line and column when available; fix the flagged spot and the code regenerates instantly.