diff --git a/pyproject.toml b/pyproject.toml
index 414346b..b306cef 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -50,7 +50,7 @@ dev = [
     "pytest-cov>=6.0.0",
     "pytest-xdist[psutil]>=3.8.0",
     "ruff>=0.11.0",
-    "sphinx>=8.2.3",
+    "sphinx>=9.0.4",
     "tox>=4.25.0",
     "tox-gh-actions>=3.5.0",
 ]