diff --git a/src/utils/front-end-cal/main.cc b/src/utils/front-end-cal/main.cc
index 42d7a7601..5d7122686 100644
--- a/src/utils/front-end-cal/main.cc
+++ b/src/utils/front-end-cal/main.cc
@@ -60,6 +60,7 @@
 #include <cstdlib>
 #include <ctime>  // for ctime
 #include <exception>
+#include <iomanip>  // for std::setiosflags, std::setprecision
 #include <iostream>
 #include <map>
 #include <memory>