TypeScript Type Generator

Paste JSON and generate TypeScript interfaces or type aliases with nested models and array inference.

JSON Input

TypeScript Output

Generation Settings

Root type name

Input parser

Declaration style

Array inference

Readonly properties

Prefix generated fields with readonly

Parser: JSON

Generated from local input only. No data is uploaded.

The TypeScript Type Generator converts JSON into ready-to-use TypeScript definitions. It handles nested objects, arrays, nullable values, and mixed array content while generating named interfaces for complex structures.

Choose parser mode (JSON, JSON5, JSONC), pick interface or type alias output, and optionally mark all fields as readonly. Use the generated output directly in frontend APIs, SDK clients, and test fixtures.

This JSON to TypeScript generator is useful when you need to quickly convert API responses into TypeScript interfacesor type aliases without manual typing. It works as a free, browser-based JSON to TypeScript tool for fast schema-to-type workflows.