diff --git a/source/utils/timedelta.cpp b/source/utils/timedelta.cpp
index 77163694..ef065efd 100644
--- a/source/utils/timedelta.cpp
+++ b/source/utils/timedelta.cpp
@@ -22,7 +22,7 @@
 // @author: see AUTHORS file
 #include <cmath>
 #include <ctime>
-#include <stdint>
+#include <cstdint>
 
 #include <xlnt/utils/timedelta.hpp>