Bridging the Backend and Frontend with Type Safety
In modern web architectures, API models and endpoints evolve rapidly. When backend teams release updated OpenAPI 3.0 or Swagger specifications, frontend engineers often spend hours manually updating TypeScript definitions, creating a vector for silent runtime type mismatches and bugs.
Why Use In-Browser Schema Compilation?
Traditional CLI code generators (such as openapi-generator-cli or heavy Java wrappers) require complex configuration files, node scripts, and local dependencies. Our 100% client-side generator provides:
- Zero Setup: Paste your JSON spec and immediately copy typed models into your project.
- Complete Data Privacy: Schema parsing executes entirely inside your browser's V8 engine. Proprietary API keys and internal business logic never leave your machine.
- Optional Typed SDK: Automatically maps endpoints into type-safe
fetch()methods with promise return types.
Supported OpenAPI Features
- Nested
$refreference model resolution (e.g.#/components/schemas/User). - String literals and string union enums (
"pending" | "approved" | "rejected"). - Automatic primitive mapping (
integerβnumber,uuid/date-timeβstring). - Array and dictionary schemas (
itemsandadditionalProperties).
Frequently Asked Questions
How do I convert an OpenAPI or Swagger JSON spec to TypeScript interfaces?
Paste your OpenAPI 3.0, 3.1, or Swagger 2.0 JSON specification into the input panel. The parser extracts all schemas from components.schemas and outputs clean TypeScript interfaces with optional fields, nested objects, and resolved $ref models instantly.
Can I generate a typed API Client Fetch SDK with this tool?
Yes! Toggle the 'Include Typed Fetch SDK' button to generate strongly-typed async fetch wrapper functions for every endpoint path defined in your specification, with path parameter interpolations and response type assertions.
Does the tool support both TypeScript 'interface' and 'type' syntax?
Yes, you can toggle between 'interface' and 'type' alias definitions with a single click, depending on your team's code conventions.
Are my proprietary API specifications uploaded to a server?
No. The entire AST schema traversal and TypeScript generation executes 100% locally in your browser memory. Your confidential internal API designs, routes, and schemas are never uploaded anywhere.
How does the generator handle required and optional fields?
The generator inspects the 'required: [...]' array in each schema definition. Properties listed in the required array receive strict typing, while omitted properties are marked with the TypeScript optional operator ('?:').
Can I download the generated definitions as a .d.ts file?
Yes, click the 'πΎ .d.ts' button to instantly export and download a production-ready 'api-types.d.ts' declaration file directly to your computer.