Postman Collection to OpenAPI
Converts a Postman Collection JSON into OpenAPI 3.0 YAML. Recursively reads nested request folders, maps URL variables and query parameters, infers schemas from raw JSON request bodies, and groups response examples under HTTP 200. Download the generated YAML locally. Input must be smaller than 10,000,000 UTF-8 bytes.
About this postman collection to openapi
Converts a Postman Collection JSON into OpenAPI 3.0 YAML. Recursively reads nested request folders, maps URL variables and query parameters, infers schemas from raw JSON request bodies, and groups response examples under HTTP 200. Download the generated YAML locally. Input must be smaller than 10,000,000 UTF-8 bytes Validates and converts interface schemas client-side without transmitting private endpoint specifications.
API contract & interface schema logic
Converts Postman Collection JSON into OpenAPI 3.0 YAML, including nested request folders, URL and query variables, schemas inferred from raw JSON request bodies, and response examples grouped under HTTP 200.
Worked schema conversion scenario
Scenario: Convert one top-level Postman request locally.
Sample input:
Processing: Read the top-level item, use its pathname and lowercased method, emit its absolute URL origin as the server, and add a placeholder 200 response.
Illustrative output:
Schema version & syntax constraints
Collection and environment variables are represented as OpenAPI server, path, or query variables when used in a URL. Raw JSON bodies are inferred from the supplied example shape; this is not full Postman or OpenAPI schema resolution. Response examples are retained under a 200 response for review.
API specifications and schema models in Postman Collection to OpenAPI reflect OpenAPI and JSON Schema standards. Verify generated schemas against your runtime validator.
Client-side schema processing boundary
Schema analysis and protocol mapping in Postman Collection to OpenAPI execute locally in the browser tab without uploading endpoint definitions.
OpenAPI Specification & JSON Schema standards
OpenAPI Specification standards and JSON Schema draft definitions:
Postman Collection to OpenAPI verification · Audit standards
How to use it
- Paste a Postman Collection JSON document with an item array.
- The converter recursively reads request folders, maps URL variables and query parameters, and infers a JSON schema from each supported raw JSON body.
- Review the generated OpenAPI YAML and download the .yaml file locally.
Frequently asked questions
How are nested requests and URL variables converted?+
The converter recursively visits folder item arrays. A URL variable used as a host becomes an OpenAPI server variable; path variables become required path parameters, and query values become query parameters.
How is a request body schema inferred?+
For a raw body containing valid JSON, the converter infers object properties, required keys, primitive types, and array item types from that sample. It does not infer a broader contract from additional requests.
Where do Postman responses and the YAML file go?+
Each saved Postman response body becomes a named example in the operation’s OpenAPI 200 response. Run the conversion, review the YAML output, then use Download OpenAPI YAML to save postman-to-openapi.yaml.
What input and schema cases are supported?+
Input must be a JSON object containing an item array; items must be requests or folders with item arrays. Collection and embedded environment variables used in URLs are mapped. This does not resolve every Postman feature or infer a full OpenAPI contract.