diff --git a/Source/Utility/MD5.cpp b/Source/Utility/MD5.cpp
new file mode 100644
index 0000000..a8efa61
--- /dev/null
+++ b/Source/Utility/MD5.cpp
@@ -0,0 +1,48 @@
+#include "Utility/MD5.h"
+
+#include <cstring>
+#include <cwchar>
+#include <windows.h>
+
+namespace {
+  // INLINED
+  inline std::uint32_t FoldDigest(const unsigned char* digest) {
+    return ((digest[0] ^ digest[1] ^ digest[2] ^ digest[3]) << 8)
+      | (digest[4] ^ digest[5] ^ digest[6] ^ digest[7])
+      | ((digest[8] ^ digest[9] ^ digest[10] ^ digest[11]) << 16)
+      | (static_cast<std::uint32_t>(digest[12] ^ digest[13] ^ digest[14] ^ digest[15]) << 24);
+  }
+}
+
+// FUNCTION: fn_00121
+MD5::MD5() {
+}
+
+
+
+
+#define MD5_F1(x, y, z) ((z) ^ ((x) & ((y) ^ (z))))
+#define MD5_F2(x, y, z) ((y) ^ ((z) & ((x) ^ (y))))
+#define MD5_F3(x, y, z) ((x) ^ (y) ^ (z))
+#define MD5_F4(x, y, z) ((y) ^ ((x) | ~(z)))
+#define MD5_STEP(f, a, b, c, d, x, s, t) do { \
+  (a) += f((b), (c), (d)) + (x) + (t); \
+  (a) = (((a) << (s)) | ((a) >> (32 - (s)))) + (b); \
+} while (0)
+
+
+#undef MD5_STEP
+#undef MD5_F4
+#undef MD5_F3
+#undef MD5_F2
+#undef MD5_F1
+
+
+
+
+
+
+
+
+
+
diff --git a/Source/Utility/MD5.h b/Source/Utility/MD5.h
new file mode 100644
index 0000000..116701b
--- /dev/null
+++ b/Source/Utility/MD5.h
@@ -0,0 +1,37 @@
+#ifndef RAGNAROK_SOURCE_UTILITY_MD5_H
+#define RAGNAROK_SOURCE_UTILITY_MD5_H
+
+#include <cstdint>
+
+class MD5 {
+public:
+  MD5();
+  ~MD5();
+
+  int Initialize();
+  void Update(const unsigned char* input, std::uint32_t length);
+  unsigned char* Finalize();
+  unsigned char* DigestBuffer(const unsigned char* input, std::uint32_t length, unsigned char* digest);
+  std::uint32_t HashBuffer(const unsigned char* input, std::uint32_t length);
+  std::uint32_t HashString(const char* text);
+  std::uint32_t HashString(const wchar_t* text);
+  std::uint32_t HashFile(const wchar_t* filename);
+  std::uint32_t HashStringLower(const char* text);
+  std::uint32_t HashStringLower(const wchar_t* text);
+  std::uint32_t HashFile(const char* filename);
+
+private:
+  const unsigned char* Decode(std::uint32_t* output, const unsigned char* input, std::uint32_t count);
+  std::uint32_t* Transform(std::uint32_t* state, const std::uint32_t* input);
+
+  union {
+    /* 0000 */ unsigned char m_buffer[64];
+    /* 0000 */ std::uint32_t m_words[16];
+  };
+  /* 0040 */ std::uint32_t m_state[4];
+  /* 0050 */ std::uint32_t m_byteCount[2];
+};
+
+static_assert(sizeof(MD5) == 0x58);
+
+#endif
diff --git a/compile.json b/compile.json
index 1983a8c..49b4d91 100644
--- a/compile.json
+++ b/compile.json
@@ -574,6 +574,7 @@
   "Source/Utility/Async/NRecycleObjectPoolMgr.cpp": 0,
   "Source/Utility/Base64.cpp": 0,
   "Source/Utility/GuidParse.cpp": 0,
+  "Source/Utility/MD5.cpp": 0,
   "Source/Utility/Math/AffineLookAt.cpp": 0,
   "Source/Utility/Math/AffineMatrix.cpp": 0,
   "Source/Utility/Math/ClientAngles.cpp": 0,