📦 JSON Schema to Code Generator

What is JSON Schema to Code Generation?

JSON Schema is a vocabulary that lets you annotate and validate JSON documents. It describes the shape of your data: which fields exist, what types they hold, which ones are required, and what constraints apply. While JSON Schema is excellent for validation and documentation, developers ultimately need typed code in their programming language of choice. Manually translating a schema with dozens of nested objects, optional fields, and array types is tedious and error-prone.

A schema-to-code generator automates this translation. It reads your JSON Schema and produces idiomatic type definitions, including interfaces for TypeScript, dataclasses for Python, structs for Go and Rust, and classes for Java and C#. The generated code respects required versus optional fields, preserves description comments, resolves local references, and handles complex constructs like union types, enums, and maps. This tool handles all of that directly in the browser with zero server calls.

Whether you are consuming a third-party API, building a new microservice, or migrating between languages, having accurate type definitions from the start eliminates a whole class of runtime bugs. Instead of guessing field names or forgetting an optional check, you get compile-time safety from day one.

How to Use This Tool

1. Paste or type your JSON Schema into the input panel on the left. You can also click one of the sample buttons to load a pre-built schema.
2. Select your target language using the tabs above the output panel: TypeScript, Python, Go, Rust, Java, or C#.
3. Adjust options as needed: set the root type name, toggle export modifiers, enable or disable description comments, and choose whether optional fields get language-specific markers.
4. Click "Generate Code" or simply switch tabs to see the output. The generated code appears instantly in the right panel with syntax highlighting.
5. Click "Copy Output" to copy the code to your clipboard, ready to paste into your project.

Key Features

• Six Target Languages - Generate TypeScript interfaces, Python dataclasses, Go structs with JSON tags, Rust structs with serde attributes, Java classes, and C# classes from a single schema.
• Full JSON Schema Support - Handles properties, required arrays, nested objects, typed arrays, enums, $ref references, definitions, oneOf/anyOf unions, additionalProperties, format hints, and description comments.
• Idiomatic Output - Each language gets its natural patterns. TypeScript uses optional chaining with question marks, Python uses Optional from typing, Go uses pointer types and json struct tags, Rust uses Option with serde, Java uses nullable annotations, and C# uses nullable reference types.
• Customizable Options - Control the root type name, toggle export or public modifiers, include or exclude description comments, and enable optional field markers.
• 100% Client-Side - All generation runs in your browser using plain JavaScript. No data is uploaded, no external services are called, and the tool works offline after the page loads.
• Sample Schemas Included - Four built-in sample schemas let you explore the tool immediately: User Profile, API Response, E-commerce Product, and Blog Post.

Frequently Asked Questions

Which JSON Schema draft does this tool support?

The tool supports the most commonly used features from JSON Schema Draft 7 and Draft 2020-12, including type, properties, required, items, enum, $ref with definitions or $defs, oneOf, anyOf, additionalProperties, description, and format. It focuses on the structural features that map directly to code types.

How does the tool handle $ref references?

Local references like #/definitions/Address or #/$defs/Address are resolved by looking up the referenced definition within the same schema document. The referenced type is generated as a separate named type, and fields that use the reference will point to that type by name. External URL references are not currently supported.

What happens with oneOf and anyOf?

Union types are generated using language-appropriate syntax. TypeScript produces union types with the pipe operator, Python uses the Union type from typing, Go uses interface{} (any), Rust generates an enum with variants, Java uses Object, and C# uses object. When the union members are simple types, they are listed directly. When they include object types, separate named types are generated for each variant.

Can I use the generated code in production?

Yes. The generated code is standard, idiomatic output for each language with no special dependencies. You may want to review and adjust it to fit your project conventions, add validation logic, or integrate it with your ORM or serialization framework. The tool gives you a solid starting point that you can customize as needed.

Is my schema data safe?

Absolutely. All processing happens entirely in your browser. Your schema is never sent to any server, stored in any database, or shared with any third party. You can verify this by using your browser's network inspector while using the tool.