diff --git a/CMakeLists.txt b/CMakeLists.txt
index 9a0907fc..1f0be243 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -36,6 +36,7 @@ include(CheckLibraryExists)
 include(CheckIncludeFile)
 include(CheckSymbolExists)
 include(CheckTypeSize)
+include(TestBigEndian)
 
 project(getdns VERSION ${PACKAGE_VERSION})
 
@@ -88,6 +89,9 @@ elseif (UNIX)
   endif()
 endif ()
 
+test_big_endian(TARGET_IS_BIG_ENDIAN)
+set(HAVE_TARGET_ENDIANNESS 1)
+
 # File locations
 set(TRUST_ANCHOR_FILE "${CMAKE_INSTALL_FULL_SYSCONF_DIR}/unbound/getdns-root.key")
 set(GETDNS_FN_RESOLVCONF "${CMAKE_INSTALL_FULL_SYSCONF_DIR}/resolv.conf")
diff --git a/cmake/include/cmakeconfig.h.in b/cmake/include/cmakeconfig.h.in
index e7b6082a..941108f5 100644
--- a/cmake/include/cmakeconfig.h.in
+++ b/cmake/include/cmakeconfig.h.in
@@ -155,6 +155,9 @@
 
 #cmakedefine STRPTIME_WORKS		1
 
+#cmakedefine HAVE_TARGET_ENDIANNESS
+#cmakedefine TARGET_IS_BIG_ENDIAN
+
 #ifdef HAVE___FUNC__
 #define __FUNC__ __func__
 #else