diff --git a/src/headers/tomcrypt_cfg.h b/src/headers/tomcrypt_cfg.h
index 87c1bf09..35af3008 100644
--- a/src/headers/tomcrypt_cfg.h
+++ b/src/headers/tomcrypt_cfg.h
@@ -79,15 +79,15 @@ LTC_EXPORT int   LTC_CALL XSTRCMP(const char *s1, const char *s2);
  * The x86 platforms allow this but some others [ARM for instance] do not.  On those platforms you **MUST**
  * use the portable [slower] macros.
  */
-/* detect x86/i386 32bit */
-#if defined(__i386__) || defined(__i386) || defined(_M_IX86)
+/* detect x86/i386/ARM 32bit */
+#if defined(__i386__) || defined(__i386) || defined(_M_IX86) || defined(_M_ARM)
    #define ENDIAN_LITTLE
    #define ENDIAN_32BITWORD
    #define LTC_FAST
 #endif
 
-/* detect amd64/x64 */
-#if defined(__x86_64__) || defined(_M_X64) || defined(_M_AMD64)
+/* detect amd64/x64/arm64 */
+#if defined(__x86_64__) || defined(_M_X64) || defined(_M_AMD64) || defined(_M_ARM64)
    #define ENDIAN_LITTLE
    #define ENDIAN_64BITWORD
    #define LTC_FAST
@@ -195,7 +195,8 @@ LTC_EXPORT int   LTC_CALL XSTRCMP(const char *s1, const char *s2);
       defined(__BYTE_ORDER__) && __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__ || \
       defined(__LITTLE_ENDIAN__) || \
       defined(__ARMEL__) || defined(__THUMBEL__) || defined(__AARCH64EL__) || \
-      defined(_MIPSEL) || defined(__MIPSEL) || defined(__MIPSEL__)
+      defined(_MIPSEL) || defined(__MIPSEL) || defined(__MIPSEL__) || \
+      defined(_M_ARM) || defined(_M_ARM64)
     #define ENDIAN_LITTLE
   #else
     #error Cannot detect endianness
@@ -219,7 +220,7 @@ LTC_EXPORT int   LTC_CALL XSTRCMP(const char *s1, const char *s2);
     defined(__s390x__) || defined(__arch64__) || defined(__aarch64__) || \
     defined(__sparcv9) || defined(__sparc_v9__) || defined(__sparc64__) || \
     defined(__ia64) || defined(__ia64__) || defined(__itanium__) || defined(_M_IA64) || \
-    defined(__LP64__) || defined(_LP64) || defined(__64BIT__)
+    defined(__LP64__) || defined(_LP64) || defined(__64BIT__) || defined(_M_ARM64)
    typedef unsigned ulong32;
    #if !defined(ENDIAN_64BITWORD) && !defined(ENDIAN_32BITWORD)
      #define ENDIAN_64BITWORD