diff --git a/pyproject.toml b/pyproject.toml
index e908fc7..8630080 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -35,7 +35,7 @@ dependencies    = [
 
 [project.optional-dependencies]
 black = [
-    "black==26.3.1",
+    "black==26.5.0",
 ]
 ruff = [
     "ruff==0.15.13",
diff --git a/requirements_black.txt b/requirements_black.txt
index eb1f300..d424915 100644
--- a/requirements_black.txt
+++ b/requirements_black.txt
@@ -1 +1 @@
-black==26.3.1
+black==26.5.0