diff --git a/pyproject.toml b/pyproject.toml
index 285547d..51e2c68 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -45,7 +45,7 @@ test = [
     "kago-utils>=0.1.4",
 ]
 docs = [
-    "sphinx>=8.2.3,<9",
+    "sphinx>=9.1.0,<10",
     "sphinx-rtd-theme>=3.1.0,<4",
 ]
 typing = [