diff --git a/docs/requirements.txt b/docs/requirements.txt
index 468249c..d20ab8d 100644
--- a/docs/requirements.txt
+++ b/docs/requirements.txt
@@ -2,5 +2,5 @@ alabaster<0.8
 jinja2<3.2
 markupsafe<2
 readme-renderer<23
-sphinx>=5,<6
+sphinx>=5,<9
 sphinxcontrib-websupport<1.2