diff --git a/docs/requirements.txt b/docs/requirements.txt
index 1313f82..7fd539a 100644
--- a/docs/requirements.txt
+++ b/docs/requirements.txt
@@ -3,6 +3,6 @@
 #
 # SPDX-License-Identifier: MIT
 
-sphinx~=8.1
+sphinx~=9.1
 sphinxcontrib-jquery~=4.1
 sphinx-rtd-theme~=3.0