diff --git a/pyproject.toml b/pyproject.toml
index bf15de1..030c762 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -60,5 +60,5 @@ dev-dependencies = [
     "pyright>=1.1.356",
     "pytest==8.3.3",
     "ruff==0.6.9",
-    "tox==4.18.1",
+    "tox==4.21.2",
 ]