API spec generator — plain lines to OpenAPI 3.1
Describe your endpoints in plain lines like GET /users - list users and get a valid OpenAPI 3.1 YAML skeleton. It generates entirely in your browser (0 uploads, works offline).
How to use it
- Write one endpoint per line: method, path and an optional summary.
- Set the API title and version.
- Copy or Download the OpenAPI YAML.
FAQ
How do I generate an OpenAPI spec quickly for free?
List your endpoints as METHOD /path - summary, one per line. This page groups them by path and emits an OpenAPI 3.1 document with a stub 200 response for each — on your device with no upload.
What line format does it expect?
A method (GET, POST, PUT, PATCH, DELETE, HEAD or OPTIONS), a path, and an optional summary after a dash or colon. Lines it does not recognise are skipped.
Is my input uploaded anywhere?
No. Generation runs entirely in your browser and nothing is transmitted or stored, which you can verify by turning off your Wi-Fi.
Is the output ready to use?
It is a valid starting skeleton with paths, methods and summaries. Add parameters, request bodies and detailed responses to complete it.
Limits
Scaffolds paths, methods and a stub response; request/response schemas and parameters are left for you to fill in.
Related
The OpenAPI viewer lists endpoints from an existing spec; the cURL-to-code tool converts requests.
Bookmark this page (Ctrl+D, or ⌘D on Mac) or install the app — it works offline the next time you need it.