diff --git a/platform/platform_mac.mm b/platform/platform_mac.mm
index ae406f3caa..1005472c29 100644
--- a/platform/platform_mac.mm
+++ b/platform/platform_mac.mm
@@ -2,6 +2,9 @@
 
 #include "../base/logging.hpp"
 
+#include "../coding/sha2.hpp"
+#include "../coding/base64.hpp"
+
 #include "../std/target_os.hpp"
 
 #include <IOKit/IOKitLib.h>
@@ -86,7 +89,16 @@ string Platform::UniqueClientId() const
   CFStringRef uuidCf = (CFStringRef) IORegistryEntryCreateCFProperty(ioRegistryRoot, CFSTR(kIOPlatformUUIDKey), kCFAllocatorDefault, 0);
   IOObjectRelease(ioRegistryRoot);
   char buf[513];
-  CFStringGetCString(uuidCf, buf, 512, kCFStringEncodingMacRoman);
+  CFStringGetCString(uuidCf, buf, 512, kCFStringEncodingUTF8);
   CFRelease(uuidCf);
-  return buf;
+
+  // generate sha2 hash for UUID
+  string const hash = sha2::digest256(buf, false);
+  // xor it
+  size_t const offset = hash.size() / 4;
+  string xoredHash;
+  for (size_t i = 0; i < offset; ++i)
+    xoredHash.push_back(hash[i] ^ hash[i + offset] ^ hash[i + offset * 2] ^ hash[i + offset * 3]);
+  // and use base64 encoding
+  return base64::encode(xoredHash);
 }