diff --git a/readthedocs.yml b/readthedocs.yml
index 973751e2..8d047bd3 100644
--- a/readthedocs.yml
+++ b/readthedocs.yml
@@ -1,5 +1,5 @@
 version: 2
-formats: []
+formats: [pdf]
 
 sphinx:
   configuration: docs/conf.py