OpenAPI Mock Generator — Turn API Specs into Live Mock Servers
Paste an OpenAPI 3.x or Swagger 2.0 spec, select any endpoint, and instantly get a realistic mock request body and response matching the defined schemas. Also generates a ready-to-run cURL command.
How to Use OpenAPI Mock Generator — Turn API Specs into Live Mock Servers
How to Use the OpenAPI Mock Response Generator
Step 1: Paste Your OpenAPI Spec
Paste an OpenAPI 3.x (JSON or YAML) or Swagger 2.0 spec into the input. Use the example buttons to load a ready-made spec and explore the tool.
Step 2: Select an Endpoint
Once the spec is parsed, a dropdown lists every path and HTTP method defined in the spec. Select the endpoint you want to test.
Step 3: Get Your Mock Data
The tool instantly generates:
- Path parameters — substituted with realistic values based on the schema
- Query parameters — filled with type-appropriate examples
- Request body — a fully populated JSON object matching the request schema
- Response body — the first successful (2xx) response body filled with mock data
- cURL command — a copy-paste-ready curl invocation with the mock request body
How Mock Values Are Generated
format: email→user@example.comformat: date-time→ ISO 8601 timestampformat: uuid→ standard UUID placeholder- Property named
name→Jane Doe - Property named
status→active enumfields → first allowed value$refschemas are fully resolvedallOf,oneOf,anyOfare handled
Tips
- Paste your actual production spec to generate mocks for your own API
- Use the cURL command to test endpoints directly in your terminal
- Both JSON and YAML specs are supported
Frequently Asked Questions
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