OpenAPI Stub Generator

Build OpenAPI 3 YAML stubs for REST APIs

Build OpenAPI 3 YAML stubs for REST APIs OpenAPI Stub Generator on Fneno helps you build openapi 3 yaml stubs for rest apis with a clean, mobile-friendly interface. Runs in your browser with strong privacy — your code and data are not stored on our servers for typical use. Used by front-end, back-end, and DevOps professionals who need fast utilities without installing software. Fneno.com is a free bilingual online toolkit — open the tool and start instantly with no signup for normal use. Runs entirely client-side in the browser — zero server upload, maximum privacy for your code and data. Free developer tool with no account required — copy results in one click, share via URL. Trusted by front-end developers, back-end engineers, sysadmins, and DevOps teams worldwide. Works on Windows, macOS, and Linux — any device with a modern browser.