diff --git a/cmd/mmv/main.go b/cmd/mmv/main.go
index 11a0ec2..26b02b8 100644
--- a/cmd/mmv/main.go
+++ b/cmd/mmv/main.go
@@ -60,7 +60,7 @@ Options:
 	}
 	args = fs.Args()
 	if len(args) == 0 {
-		fmt.Printf("usage: %s files ...\n", name)
+		fmt.Fprintf(os.Stderr, "usage: %s files ...\n", name)
 		return exitCodeErr
 	}
 	if err := rename(args); err != nil {