What is an OpenAPI / Swagger Viewer?
An OpenAPI / Swagger Viewer turns a JSON or YAML API specification into a readable browser view so developers can review operations, schemas, and documentation quality.
OpenAPI / Swagger Viewer
Paste an OpenAPI or Swagger spec and inspect endpoints, methods, schemas, parameters, and responses in your browser.
Spec input
JSON and YAML OpenAPI 3.x or Swagger 2.0 documents. Remote references are detected, not fetched.
Inspection report
Readable API summary, endpoint browser, reusable components, and validation hints.
Ready to inspect an API spec
Paste JSON or YAML, load a sample, then inspect paths, methods, parameters, responses, schemas, and warnings without calling any API.
OpenAPI Inspection Guide
Browse API specs without executing them
Use this viewer to understand pasted API descriptions locally: endpoints, methods, parameters, responses, reusable schemas, security schemes, and common documentation gaps.
OpenAPI 3 vs Swagger 2
Swagger 2.0 uses fields such as swagger, host, basePath, and definitions. OpenAPI 3.x uses openapi, servers, components, and richer request body modeling.
How to inspect endpoints and schemas
Paste a spec, choose Inspect spec, then search by path, method, tag, operationId, parameter, or response text. Select an operation to review its request and response details.
Common OpenAPI validation issues
Frequent issues include missing info.title, missing info.version, empty paths, duplicate or missing operationId, missing response descriptions, and unresolved local references.
Why remote refs are not fetched
Remote $ref values can point to private networks or external services. This viewer reports them but does not fetch them, keeping inspection local and predictable.
OpenAPI Viewer vs JSON/YAML Formatter
Formatters make raw JSON or YAML easier to read. This viewer understands OpenAPI structure and extracts API-specific summaries, endpoint lists, components, and validation hints.
Private and internal APIs
Specs can contain internal paths, hosts, schema names, and security scheme details. Processing stays in the browser, but review reports before sharing them outside your team.
OpenAPI / Swagger Viewer FAQ
Does this OpenAPI Viewer upload my API spec?
No. Parsing and inspection run locally in your browser.
Does it call my API endpoints?
No. This tool only reads the pasted specification. It does not execute operations, examples, servers, links, callbacks, or external docs.
Does it support YAML specs?
Yes. Paste JSON or YAML OpenAPI and Swagger specs. The viewer auto-detects the format where practical.
What is the difference between OpenAPI and Swagger?
Swagger 2.0 is the older specification name and format. OpenAPI 3.x is the modern successor with expanded components, servers, request bodies, and schema support.
Does it support OpenAPI 3.1?
Yes. The viewer detects OpenAPI 3.1.x and extracts endpoints, components, schemas, responses, parameters, and security schemes.
Are remote $ref values resolved?
No. Remote references are reported as warnings but are never fetched. Local references inside the pasted document are checked when practical.