diff --git a/API.md b/API.md
index 64c8aebd..e88b3224 100644
--- a/API.md
+++ b/API.md
@@ -16,6 +16,7 @@ Current websites using this API:
 - [picocolors-size-benchmark](https://github.com/alexeyraspopov/picocolors/pull/76)
 - [dependencies-dashboard](https://github.com/shakib1729/dependencies-dashboard-main)
 - [https://jsgrids.statico.io](https://github.com/statico/jsgrids/commit/bb8069627d4d9a9b158ffb6324054399ef8d0433)
+- [npm-diff.app](https://github.com/oBusk/npm-diff.app/commit/d91f188458ac6eeae1cdc54f8a8e2be7fd81d7aa)
 
 ## Endpoints