JSON to TypeScript Interface Generator
Paste any JSON object and get TypeScript interfaces instantly — nested types, arrays, and optional fields included.
Root interface name
Optional fields
Export
JSON Input
TypeScript Output
Paste any JSON object and get TypeScript interfaces instantly — nested types, arrays, and optional fields included.
Root interface name
Optional fields
Export
JSON Input
TypeScript Output
In short: A JSON to TypeScript generator reads a JSON object and produces matching TypeScript interfaces — inferring types for nested objects, arrays, and primitives so you don't have to write them by hand. RealJSON's generator does this instantly in your browser, with optional fields and export keywords toggleable.
TypeScript's type system is one of the biggest productivity wins in modern frontend and backend development — but manually writing interfaces for every API response or config object wastes time and introduces errors. This tool generates TypeScript interfaces directly from any JSON object, handling nested types, arrays, and primitive inference automatically.
Paste a JSON payload from your API, set your root interface name, and get clean, copyable TypeScript in seconds. Works entirely in your browser — no data is ever sent to a server.
Each nested object becomes its own named interface, inferred from the key name and placed above the parent interface for correct TypeScript ordering.
Arrays are typed as T[] with the element type inferred from the array's contents — including arrays of objects, which become typed interface arrays.
Toggle "Mark all fields optional" to add ? to every field — useful for partial API payloads or update request bodies where not every field is required.
Toggle the export flag to prefix every interface with export so they can be imported across your TypeScript project.
Paste a JSON object, set a root interface name, and TypeScript interfaces are generated instantly — including nested types and arrays. Copy the result or download it as a .ts file.
Each nested object becomes its own named interface, inferred from its key name and ordered above the parent so the generated TypeScript compiles correctly.
Arrays are typed as T[], with the element type inferred from the array's contents — including arrays of objects, which become typed interface arrays.
Yes. Toggle "Mark all fields optional" to add a ? to every field — handy for partial API payloads or PATCH/update bodies where fields aren't guaranteed.
No. Generation happens entirely in your browser — your JSON never leaves your device.
Use the JSON Validator to verify your payload before generating types, or the JSON Formatter to clean it up first.
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