diff --git a/src/endianness.h b/src/endianness.h
new file mode 100644
index 0000000..f3532d5
--- /dev/null
+++ b/src/endianness.h
@@ -0,0 +1,7 @@
+#ifndef ENDIANNESS_H
+#define ENDIANNESS_H
+
+#define IS_LITTLE_ENDIAN ((*(uint8_t *)(&(uint32_t){0x00010203})) == 0x03)
+#define IS_BIG_ENDIAN ((*(uint8_t *)(&(uint32_t){0x00010203})) == 0x00)
+
+#endif // !ENDIANNESS_H