Generator Options
JSON to TypeScript Type Mapping
JSON string
→ string
JSON number
→ number
JSON boolean
→ boolean
JSON null
→ null
How to Convert JSON to TypeScript Online
- 1
Paste Your JSON Data
Copy any valid JSON from an API response, configuration file, or database export and paste it into the JSON Input panel. The tool accepts objects, arrays, and nested structures of any complexity. - 2
Configure Generator Options
Choose between interface or type alias output. Set the root interface name, select a naming convention like PascalCase, and toggle options such as export keyword, optional properties, or inline nested types to match your project style. - 3
Review the Generated TypeScript
The TypeScript Output panel updates in real time as you type or change settings. Each nested object becomes a separate named interface by default. Check that property names and types match your expectations. - 4
Copy and Use in Your Project
Click the Copy button to copy the generated interfaces to your clipboard. Paste them into any .ts or .d.ts file in your TypeScript project. The types are production-ready and work with any TypeScript version 2.0 or later.
Use Cases for JSON to TypeScript Conversion
Typing REST API Responses
Configuration File Typing
Database Schema Prototyping
Third-Party SDK Integration
Why use JSON to TypeScript Generator?
The JSON to TypeScript generator converts raw JSON data into clean, production-ready TypeScript interfaces or type aliases. Whether you are integrating a REST API, typing a configuration file, or scaffolding types for a new database schema, this tool eliminates the tedious process of writing interfaces by hand. Paste your JSON, configure the output style, and copy type-safe definitions directly into your project. Everything runs in your browser with no data uploaded to any server.
The generator handles real-world complexity including deeply nested objects, mixed-type arrays, nullable fields, and empty collections. Each nested structure becomes a separately named interface for maximum reusability, or you can enable inline mode to keep everything in a single root type. Customizable options like PascalCase naming, export keywords, and optional property markers let you match any team's coding standards. Pair it with the JSON Formatter to clean up messy API responses before conversion, or use the JSON Schema Generator to produce a formal schema alongside your TypeScript types.
For projects that span multiple languages, convert the same JSON to type-safe definitions in Go structs, Java classes, or Python dataclasses. If you need runtime validation on top of static types, the JSON to Zod Schema tool generates Zod schemas that pair perfectly with your TypeScript interfaces. All tools are free, require no signup, and process data entirely client-side.
How It Compares
CLI tools like quicktype and json2ts can generate TypeScript interfaces from JSON, but they require Node.js installation, terminal setup, and project configuration. IDE extensions such as Paste JSON as Code in VS Code handle simple cases but struggle with deeply nested objects and offer limited formatting options. Paid API platforms like Postman and Insomnia generate types as part of broader toolchains but lock features behind subscriptions.
This JSON to TypeScript generator fills the gap as a free, zero-install, browser-based tool that handles complex nesting, union types, and nullable fields out of the box. It supports both interface and type alias output, configurable naming conventions, optional properties, inline nesting, and export keywords. While it does not replace a full code generation pipeline for enterprise schemas, it provides the fastest path from raw JSON to production-ready TypeScript types for everyday development work.