What JSON to OpenAPI does
Turn an example payload into an OpenAPI 3.1 document with an inferred schema, path parameters, and a response example.
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Infer a JSON Schema from the payload
Wrap it in an OpenAPI operation
Add the servers, tags, auth, and error responses you declare
The payload is only the success case
One example shows the shape of a 200 and nothing else. Servers, tags, a security scheme, query parameters, and the error responses are the parts a reviewer asks for, so each is a field you fill in rather than something the tool invents.
Still a draft
An example cannot reveal which fields are optional. Everything arrives required — relax what can legitimately be absent before clients depend on it.
JSON to OpenAPI FAQ
Does jsontools.me upload my JSON?
No. The document is parsed and processed by json-buf inside a dedicated WebAssembly worker on your device.
Does it work offline?
Yes. After the application shell and engine have loaded once, the installable PWA keeps the tools available without a network connection.