How to Explore an OpenAPI Specification
Use the OpenAPI Viewer to navigate API endpoints, understand request and response schemas, and read authentication requirements — all in your browser.
Tool Used
OpenAPI / Swagger Viewer
Load your OpenAPI specification
Open the OpenAPI Viewer tool. Paste your OpenAPI YAML or JSON into the input field, or upload a .yaml or .json file. The viewer supports OpenAPI 3.0, 3.1, and Swagger 2.0. If you do not have a spec, try one of the sample specs provided in the tool — the Petstore or a public API spec are good starting points.
Browse endpoints in the sidebar
After loading, the left sidebar shows all endpoints organized by tag. Click a tag to expand the group and see the endpoints it contains. Each endpoint is labeled with its HTTP method (GET, POST, PUT, DELETE) and path. Click any endpoint to jump to its detail view.
Read the endpoint detail
The endpoint detail view shows: the HTTP method and full path, a summary and description, all parameters (path, query, header, cookie) with their types and whether they are required, the request body schema for POST/PUT/PATCH endpoints, and all response codes with their schemas. Read through each section to understand what the endpoint expects and what it returns.
Explore schemas in components
Click any $ref link in a schema to jump to the referenced component definition. The components section contains reusable schemas that represent the data models of the API. Reading these gives you a clear picture of the API's data model without reading each endpoint individually.
Check security requirements
Look at the security section at the top level and on individual endpoints. An endpoint may require a bearer token, an API key, OAuth2 scopes, or no authentication. The viewer highlights these requirements clearly. Compare with the securitySchemes in the components section to understand how to obtain the required credentials.
All done!
You are ready to use OpenAPI / Swagger Viewer like a pro.