What OpenAPI version does it generate?

It generates OpenAPI 3.1.0 specifications (paths, responses, and schemas) from your form input, ready to copy or download.

Can I preview the API documentation?

The spec is generated as YAML text that you can drop into Swagger UI, Redoc, or any OpenAPI viewer. The tool itself focuses on fast, correct spec generation.

devvkit / generators

OpenAPI Spec Generator

Generate OpenAPI 3.1 specifications from sample data.

Endpoints

Input

Generated OpenAPI Spec

openapi: 3.1.0
info:
  title: API Specification
  description: Generated by devvkit
  version: 1.0.0
servers:
  - url: https://api.example.com/v1
paths:
  /users:
    get:
      summary: List all users
      operationId: get_users
      responses:
        '200':
          description: Successful response
          content:
            application/json:
              schema: {"type":"array","items":{"$ref":"#/components/schemas/User"}}
              example: [{"id":1,"name":"John","email":"john@example.com"}]
  /users/{id}:
    get:
      summary: Get a user by ID
      operationId: get_users_id
      responses:
        '200':
          description: Successful response
          content:
            application/json:
              schema: {"type":"object","$ref":"#/components/schemas/User"}
              example: {"id":1,"name":"John","email":"john@example.com"}
  /users:
    post:
      summary: Create a new user
      operationId: post_users
      responses:
        '200':
          description: Successful response
          content:
            application/json:
              schema: {"type":"object","$ref":"#/components/schemas/User"}
              example: {"id":2,"name":"Jane","email":"jane@example.com"}
components:
  schemas:

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Build and edit OpenAPI 3.0 and 3.1 specifications with an interactive editor. Define endpoints, schemas, parameters, and responses with live validation and preview.

>[x]Features

-Supports OpenAPI 3.0 and 3.1 specifications
-Interactive editor with endpoint and schema definitions
-Live validation with detailed error reporting
-Preview generated API documentation
-Import existing OpenAPI YAML or JSON specs
-Export as YAML or JSON for direct use

>>Use Cases

>Designing RESTful API contracts before implementation
>Documenting existing APIs with OpenAPI specification
>Drafting path and schema definitions before coding the API
>Sharing a spec skeleton with backend teammates

OpenAPI Spec Generator

Frequently Asked Questions