diff --git a/services/backup/src/Tools.cpp b/services/backup/src/Tools.cpp
--- a/services/backup/src/Tools.cpp
+++ b/services/backup/src/Tools.cpp
@@ -3,6 +3,7 @@
 #include "GlobalConstants.h"
 #include "GlobalTools.h"
 
+#include <algorithm>
 #include <chrono>
 #include <cstdlib>
 #include <random>
@@ -52,6 +53,22 @@
   return result;
 }
 
+std::size_t getUtf8Length(std::string &str) {
+
+  // How it works?
+  // Every byte of multibyte utf8 character starts with information about its
+  // own type. Additional bytes always start with a 2bit sequence "10xx xxxx"
+  // (which is equal to hex 0x80). To count the length of utf8 string we need
+  // to skip these bytes, so we use a bitmask.
+  //
+  // We need to compare first 2 bits of a byte, so we use bitwise operator
+  // & with mask 0xC0. If returned value is equal to 0x80, we skip it.
+
+  return std::count_if(str.begin(), str.end(), [](char c) {
+    return (static_cast<unsigned char>(c) & 0xC0) != 0x80;
+  });
+}
+
 } // namespace tools
 } // namespace network
 } // namespace comm