API Mock Server Config Generator — Build Instant Mock Endpoints Online
Paste API route definitions to instantly generate JSON configuration files for json-server, Mockoon, and Prism mock servers. Define routes as METHOD /path lines and get ready-to-use config with realistic sample data.
How to Use API Mock Server Config Generator — Build Instant Mock Endpoints Online
How to Use the Mock Server Config Generator:
Load an Example or Paste Routes: Click a preset (Blog API, E-commerce, Auth API, Minimal CRUD) to populate the input, or paste your own routes directly into the textarea.
Route Format: Each line should follow the format: METHOD /path — for example: GET /users or POST /users/:id. You can optionally specify a status code: DELETE /users/:id 204. Lines starting with # are treated as comments and ignored.
Supported Methods: GET, POST, PUT, PATCH, DELETE, HEAD, OPTIONS. Paths can include named parameters using :param syntax (e.g. /users/:id).
Choose Output Format:
- json-server: Generates db.json with sample data collections. Run with: npx json-server db.json
- Mockoon: Generates an environment file you can import directly into the Mockoon desktop app via Open Environment.
- Prism (OpenAPI): Generates an OpenAPI 3.0 JSON spec with examples. Run with: npx @stoplight/prism-cli mock openapi.json
Click Generate Config: The tool parses your routes, fills in realistic sample data based on resource names (users, products, orders, posts, etc.), and produces the complete config JSON.
Copy or Download: Use the Copy button to copy the JSON to your clipboard, or click the filename button (db.json, mockoon.json, openapi.json) to download the file directly.
Switch Formats: Select a different output format with the radio buttons — the config regenerates instantly without re-clicking Generate.
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