diff --git a/include/dx2/h5/h5read_processed.h b/include/dx2/h5/h5read_processed.hpp
similarity index 100%
rename from include/dx2/h5/h5read_processed.h
rename to include/dx2/h5/h5read_processed.hpp
diff --git a/include/dx2/h5/h5write.h b/include/dx2/h5/h5write.hpp
similarity index 100%
rename from include/dx2/h5/h5write.h
rename to include/dx2/h5/h5write.hpp
diff --git a/tests/test_read_h5_array.cxx b/tests/test_read_h5_array.cxx
index acef842..cedecb3 100644
--- a/tests/test_read_h5_array.cxx
+++ b/tests/test_read_h5_array.cxx
@@ -1,4 +1,4 @@
-#include <dx2/h5/h5read_processed.h>
+#include <dx2/h5/h5read_processed.hpp>
 #include <filesystem>
 #include <gtest/gtest.h>
 #include <hdf5.h>
diff --git a/tests/test_write_h5_array.cxx b/tests/test_write_h5_array.cxx
index b2e84eb..010aeb2 100644
--- a/tests/test_write_h5_array.cxx
+++ b/tests/test_write_h5_array.cxx
@@ -1,6 +1,6 @@
 #include <array>
-#include <dx2/h5/h5read_processed.h>
-#include <dx2/h5/h5write.h>
+#include <dx2/h5/h5read_processed.hpp>
+#include <dx2/h5/h5write.hpp>
 #include <filesystem>
 #include <gtest/gtest.h>
 #include <hdf5.h>