OpenAPI / Swagger Viewer

Render an OpenAPI 3.0 / 3.1 or Swagger 2.0 document (YAML or JSON) into a browsable API reference — info, servers, tagged paths, parameters, request body examples generated from schemas, responses and security. Expand any operation to Try it and send a live request from your browser, or export it as cURL. Documents are parsed locally; remote $ref targets and external schemas are not fetched (fully local). Prefer an interactive request composer instead? See the REST API Client / Tester and the whole API Tools family.
OpenAPI / Swagger document
Try it
Parameters
About this viewer: supports Swagger 2.0 and OpenAPI 3.0 / 3.1. References are resolved inside the document only (#/components/schemas/…, #/definitions/…); external file / URL references are reported rather than fetched. Try it calls are subject to the target server’s CORS policy — if a call is blocked, use the cURL Converter or REST Client to run it from outside the browser sandbox.
OpenAPI vs Swagger, v2 vs v3

Swagger was the original tooling name; when the spec format was donated to the Linux Foundation in 2015 it became OpenAPI, and Swagger lives on as a tooling brand. A document is built from info (metadata), paths (operations per endpoint) and components (reusable schemas).

The version key tells viewers which parser to use: swagger: "2.0" versus openapi: 3.0.x — v3 moved request bodies out of parameters and adopted real JSON Schema.