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Tools / JSON to TypeScript

Type Generator

JSON → TypeScript Converter

Transform raw JSON payloads into clean, strongly typed TypeScript interfaces or type definitions. Discovers optional fields across array items, sanitizes property identifiers, and formats in real-time.

JSON INPUT 592 bytes
TYPESCRIPT DEFINITIONS

Why Type Your JSON APIs in TypeScript?

Building resilient web applications requires end-to-end type safety. Manually writing TypeScript interfaces for complex, deeply nested REST responses or GraphQL payloads is error-prone and tedious.

Interfaces vs Type Aliases

  • interface (Recommended for Objects): Extensible via declaration merging and inheritance (extends). Clean syntax for domain entities and backend response models.
  • type (Recommended for Unions & Primitives): Ideal for unions (type Status = "active" | "inactive"), tuples, and mapped types.

Features of this Generator

  • Array Property Merging: Inspects every object inside an array. If field email appears in record 1 but not record 2, it is automatically marked optional (email?: string).
  • Identifier Sanitization: Automatically wraps non-standard keys like "content-type" in quotes while keeping valid identifiers unquoted.
  • 100% Client-Side: Conversions happen instantaneously inside your browser using V8's native parser. No sensitive customer payload is ever sent to an external server.