API & OpenAPI utility

OpenAPI Migration Report

Summarize endpoint, component schema, version, and server URL changes between two specifications.

● This tool runs entirely in your browser. Your input is never uploaded to our servers.

OpenAPI YAML or JSON

Output

Your result will appear here…

How to use OpenAPI Migration Report

Paste the old specification, then === TARGET ===, then the new specification.
Select Generate Report to summarize endpoint, schema, version, and server changes.
Review the full contracts and test client compatibility before release.

Example

Input:

{"openapi":"3.0.3","info":{"title":"Demo","version":"1"},"servers":[{"url":"https://api.example.com/v1"}],"paths":{"/users":{"get":{"responses":{"200":{"description":"ok"}}}}},"components":{"schemas":{"User":{"type":"object"}}}}
=== TARGET ===
{"openapi":"3.1.0","info":{"title":"Demo","version":"2"},"servers":[{"url":"https://api.example.com/v2"}],"paths":{},"components":{"schemas":{}}}

Output:

OpenAPI migration summary
Versions: 3.0.3 → 3.1.0
Server URLs: changed

Use cases

Prepare an API contract release review.
Summarize server and schema changes for consumers.
Compare old and new API documents without uploading them.

About this tool

Summarize endpoint, component schema, version, and server URL changes between two specifications. Processing happens locally in your browser, so your input is not sent to a server or included in analytics.

Frequently asked questions

Does the report prove the new API is backward compatible?

No. It is a summary and does not detect every request, response, or runtime behavior change.

Does it resolve all $ref values?

No. Schema comparisons use definitions in the pasted documents and do not resolve remote references.

How are the two documents separated?

Put === TARGET === on its own line between the old and new YAML or JSON documents.