JSON → Code Generator

Free JSON to Code Class Generator

Convert any JSON object into type-safe classes, interfaces, or structs for your favourite programming language — instantly, in your browser.

Manually writing data model classes from JSON is tedious and error-prone. This tool does it automatically: paste your JSON, choose your language, and get production-ready classes with proper types, annotations, and null-safety.

Supported Languages

• TypeScript — export interface definitions with optional properties
• Java — POJOs with Jackson @JsonProperty annotations and getters/setters
• C# — classes with [JsonPropertyName] and { get; set; }
• Go — structs with json: struct tags and exported field names
• Python — @dataclass with from typing import type hints
• Kotlin — data class with kotlinx serialization annotations
• Swift — Codable structs with CodingKeys where needed
• Rust — serde derive structs with #[serde(rename)]
• PHP 8 — typed property classes with declare(strict_types=1)

How It Works

1. Paste your JSON into the left panel (object or array of objects).
2. Set the root class name (default: Root).
3. Click a language button — code is generated instantly.
4. Copy or download the result directly.

How to Use This Tool Effectively

• Use a realistic API response sample — the more representative your JSON, the better the type inference
• For arrays, paste the full array — the tool will merge all item schemas to catch optional fields
• Rename the root class to match your domain (e.g. User, Order, Product)
• Nested objects automatically get their own named class based on the JSON key

Type Inference Rules