diff --git a/src/hashlittle.h b/src/hashlittle.h
index 75380d366b..aafde922b7 100644
--- a/src/hashlittle.h
+++ b/src/hashlittle.h
@@ -6,7 +6,7 @@
 #define LMP_HASHLITTLE_H
 
 #include <cstddef>
-#include <stdint.h>
+#include <cstdint>
 
 namespace LAMMPS_NS {
   uint32_t hashlittle(const void *key, size_t length, uint32_t);
diff --git a/src/info.cpp b/src/info.cpp
index c02a0499fc..9cb6528f7d 100644
--- a/src/info.cpp
+++ b/src/info.cpp
@@ -53,7 +53,7 @@
 #ifdef _WIN32
 #define PSAPI_VERSION 1
 #include <windows.h>
-#include <stdint.h> // <cstdint> requires C++-11
+#include <cstdint>
 #include <psapi.h>
 #else
 #include <sys/resource.h>
diff --git a/src/math_special.cpp b/src/math_special.cpp
index d4abc36f25..c8aa248910 100644
--- a/src/math_special.cpp
+++ b/src/math_special.cpp
@@ -1,6 +1,6 @@
 #include "math_special.h"
 #include <cmath>
-#include <stdint.h> // IWYU pragma: keep
+#include <cstdint> // IWYU pragma: keep
 
 using namespace LAMMPS_NS;
 
diff --git a/src/timer.cpp b/src/timer.cpp
index 0a5e56ab35..41a0166a89 100644
--- a/src/timer.cpp
+++ b/src/timer.cpp
@@ -21,7 +21,7 @@
 
 #ifdef _WIN32
 #include <windows.h>
-#include <stdint.h> // <cstdint> requires C++-11
+#include <cstdint>
 #else
 #include <sys/time.h>
 #include <sys/resource.h>