API Changelog Generator
Generate a Markdown changelog from two OpenAPI versions.
About the API Changelog Generator
Diff two OpenAPI documents and produce a release-ready Markdown changelog grouped into Breaking Changes, Added, Changed and Removed, complete with a suggested semantic version bump you can paste straight into release notes or docs.
Examples
v1 → v2
Two OpenAPI documentsOutput
SQL## Breaking Changes
- Removed `DELETE /users/{id}`Keyboard shortcuts
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Frequently asked questions
Read more
- Postman collections and OpenAPI: two views of the same API
A collection describes calls you make; a spec describes the contract you promise. Here is how to convert between them without losing the parts that matter.
Version 1.0.0 · Updated 2026-08-20 · Runs entirely in your browser