diff --git a/src/apps/cct.cpp b/src/apps/cct.cpp
index 59f00800f3..f571700503 100644
--- a/src/apps/cct.cpp
+++ b/src/apps/cct.cpp
@@ -79,6 +79,7 @@ Thomas Knudsen, thokn@sdfe.dk, 2016-05-25/2017-10-26
 #include <string.h>
 
 #include <algorithm>
+#include <cstdint>
 #include <fstream> // std::ifstream
 #include <iostream>
 
diff --git a/src/apps/cs2cs.cpp b/src/apps/cs2cs.cpp
index 27caa603cc..88353bf8f0 100644
--- a/src/apps/cs2cs.cpp
+++ b/src/apps/cs2cs.cpp
@@ -36,6 +36,7 @@
 #include <string.h>
 
 #include <cassert>
+#include <cstdint>
 #include <iostream>
 #include <string>
 #include <vector>