OpenAPI Spec Viewer

Paste an OpenAPI 3.x or Swagger 2.0 spec (JSON or YAML) and get clean, browseable API docs. Endpoints grouped by tag, parameters and request bodies expanded, response schemas visible. Useful for reviewing an unfamiliar API or sharing docs without spinning up Swagger UI.

How to use the OpenAPI Spec Viewer

Paste the full spec. JSON loads directly; YAML is parsed via a small loader. The renderer groups endpoints by their first tag, shows method + path + summary on each row, and expands parameters and request/response schemas inline.

Reading an API spec without setup

An OpenAPI or Swagger document is precise but hard to read raw — hundreds of lines of nested JSON or YAML describing paths, parameters, and schemas. The usual way to make it browseable is to stand up Swagger UI, which is overkill when you just want to understand or share an API.

Paste a spec here and it renders as clean docs: endpoints grouped by tag, each showing method, path, and summary, with parameters and request and response schemas expanded inline. JSON loads directly and YAML is parsed for you. To check a JSON request or response against its schema, pair it with the JSON Schema validator.

Common use cases

  • API review — browse an unfamiliar spec without local tooling.
  • Sharing docs — hand someone readable docs from a raw spec.
  • Endpoint lookup — find a path's parameters and response shape.
  • Spec QA — eyeball a generated spec before publishing it.
  • Onboarding — help a new developer explore an API quickly.

Frequently asked questions

What spec versions does it accept?
OpenAPI 3.x and Swagger 2.0, in either JSON or YAML.

Does my spec get uploaded?
No. It is parsed and rendered in your browser; nothing is sent to a server.

How are endpoints organized?
By their first tag, with each row showing the method, path, and summary and expandable parameter and schema details.

Can it make live API calls?
No — it's a read-only viewer for understanding and sharing a spec, not a request client.
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