OpenAPI / Swagger Preview

OpenAPI / Swagger Spec (JSON or YAML)0 chars
Paste an OpenAPI 3.x or Swagger 2.0 spec above to see interactive API documentation

Supported Features

Spec Versions

OpenAPI 3.0.x / 3.1.x and Swagger 2.0. Auto-detects JSON or YAML format.

Endpoints

GET, POST, PUT, PATCH, DELETE, OPTIONS, HEAD, TRACE. Grouped by tag with parameters, request bodies, and responses.

Schemas

Component/definition schemas with $ref resolution. Displays property types, required fields, and descriptions.

Security

HTTP Bearer, API Key, OAuth2, and OpenID Connect security scheme display.

What This Tool Does

OpenAPI / Swagger Preview is built for deterministic developer and agent workflows.

Paste an OpenAPI or Swagger spec and see interactive API documentation instantly. Free online OpenAPI viewer.

Use How to Use for execution steps and FAQ for constraints, policies, and edge cases.

Last updated:

This tool is provided as-is for convenience. Output should be verified before use in any production or critical context.

Agent Invocation

Best Path For Builders

Browser workflow

Runs instantly in the browser with private local processing and copy/export-ready output.

Browser Workflow

This tool is optimized for instant in-browser execution with local data handling. Run it here and copy/export the output directly.

/openapi-preview/

For automation planning, fetch the canonical contract at /api/tool/openapi-preview.json.

How to Use OpenAPI / Swagger Preview

  1. 1

    Paste OpenAPI or Swagger spec

    Paste your OpenAPI 3.0 or Swagger 2.0 spec (JSON or YAML). The tool parses it and generates interactive API documentation instantly.

  2. 2

    Navigate endpoints and operations

    See all endpoints organized by tags (paths, operations). Click any endpoint to expand its parameters, request body, and response schema.

  3. 3

    Test API calls with built-in client

    Click 'Try it out' on any endpoint. Fill in parameters, headers, and request body. Send the request and see the response with status code and body.

  4. 4

    View response schemas and examples

    See expected response structures for success and error cases. Review example responses to understand data format before integration.

  5. 5

    Export as curl, fetch, or SDK

    Generate code snippets for curl commands, JavaScript fetch, Python requests, or other languages. Copy and paste directly into your code.

Frequently Asked Questions

What is OpenAPI / Swagger Preview?
OpenAPI / Swagger Preview renders interactive API documentation from your OpenAPI or Swagger specification. Paste your spec and instantly see formatted endpoints, schemas, parameters, and response models.
How do I use OpenAPI / Swagger Preview?
Paste your OpenAPI 3.x or Swagger 2.0 specification in JSON or YAML format. The tool parses it and displays interactive API documentation with endpoints grouped by tags, request/response schemas, and parameter details.
Is OpenAPI / Swagger Preview free?
Yes. This tool is free to use with immediate access—no account required.
Does OpenAPI / Swagger Preview store or send my data?
No. All processing happens entirely in your browser. Your data never leaves your device — nothing is sent to any server.
Does it support both OpenAPI 3.x and Swagger 2.0?
Yes. The tool supports both OpenAPI 3.0/3.1 and legacy Swagger 2.0 specifications. It accepts both JSON and YAML formats and renders the documentation the same way regardless of the spec version.