Which languages does this tool support?

TypeScript (interface), Python (dataclass), Go (struct with json tags), Rust (struct with serde derives), Java (record), and Zod schema. Select the target language with the tabs above the output.

Does it handle nested objects?

Yes. Nested objects are recursively expanded into separate named types or structs. The root type is named Root and nested types use the field name as the type name in PascalCase.

What happens if the JSON contains an array?

Arrays are typed as typed slices, lists, or arrays in each language. If the array contains objects, the element type is inferred from the first element.

Does this work for API response bodies?

Yes. Copy the JSON response from your browser's Network tab or from a curl response, paste it here, pick your language, and you get a complete type definition ready to paste into your project.

Are null values handled?

Null fields are typed as nullable or optional in each language — Optional in Python, *Type pointers in Go, Option in Rust, and null union members in TypeScript.

Private by defaultRuns in your browser

JSON → code generator

Paste a JSON object or array and generate ready-to-use type definitions for your language of choice — no setup required.

JSON input

TypeScript output

Quick samplesUseful for testing

JSON → Code

About this tool

Paste a JSON object and get TypeScript interfaces, Python dataclasses, Go structs, Rust structs, Java records, or Zod schemas. Instant, no signup.

Paste a JSON object or array and generate ready-to-use type definitions for your language of choice — no setup required.

No signup requiredRuns in your browserInstant results

How to use

1
Paste a JSON object or array into the input field.
2
Select the target language: TypeScript, Python, Go, Java, Rust, or others.
3
The generated type definitions or structs appear instantly.
4
Click Copy to paste the generated code directly into your project.

Why use this tool?

→
Generate TypeScript interfaces from an API response to add static typing to your frontend.
→
Convert a JSON config into a Python dataclass for cleaner, type-safe configuration handling.
→
Turn a JSON payload into a Go struct with json tags for use in a REST API handler.

ExamplesInput → output

JSON to TypeScript interface

Input{"id":1,"name":"Alice","active":true}

Output

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

JSON to Python dataclass

Input{"id":1,"name":"Alice"}

Output

@dataclass
class Root:
  id: int
  name: str

Frequently asked questionsCommon questions answered

These answers explain common json → code tasks, expected input formats, and edge cases so both visitors and search engines can understand what this tool does.

Which languages does this tool support?: TypeScript (interface), Python (dataclass), Go (struct with json tags), Rust (struct with serde derives), Java (record), and Zod schema. Select the target language with the tabs above the output.
Does it handle nested objects?: Yes. Nested objects are recursively expanded into separate named types or structs. The root type is named Root and nested types use the field name as the type name in PascalCase.
What happens if the JSON contains an array?: Arrays are typed as typed slices, lists, or arrays in each language. If the array contains objects, the element type is inferred from the first element.
Does this work for API response bodies?: Yes. Copy the JSON response from your browser's Network tab or from a curl response, paste it here, pick your language, and you get a complete type definition ready to paste into your project.
Are null values handled?: Null fields are typed as nullable or optional in each language — Optional in Python, *Type pointers in Go, Option<T> in Rust, and null union members in TypeScript.