diff --git a/.env.example b/.env.example
index a241c620..85574af4 100644
--- a/.env.example
+++ b/.env.example
@@ -37,6 +37,9 @@ RUNPOD_API_KEY=
 MODAL_TOKEN_ID=
 MODAL_TOKEN_SECRET=
 
+# Raises OpenAlex rate limits and unlocks usage stats. Free key from https://openalex.org/users/me/
+OPENALEX_API_KEY=
+
 # Raises the NCBI E-utilities limit from 3 to 10 requests/sec.
 NCBI_API_KEY=
 # Optional minimum delay between NCBI request starts (500ms anonymous, 125ms keyed).