diff --git a/src/common/stringutils.cpp b/src/common/stringutils.cpp
index 5896a332..5e7afd1e 100644
--- a/src/common/stringutils.cpp
+++ b/src/common/stringutils.cpp
@@ -175,17 +175,17 @@ int StrUtils::Utf8CharSizeAt(const std::string &str, unsigned int pos)
         return 0;
 
     const char c = str[pos];
-    if(c >= 0xF0)
+    if((c & 0b11111000) == 0b11110000)
         return 4;
-    if(c >= 0xE0)
+    if((c & 0b11110000) == 0b11100000)
         return 3;
-    if(c >= 0xC0)
+    if((c & 0b11100000) == 0b11000000)
         return 2;
 
     // Invalid char - unexpected continuation byte
-    if(c >= 0x80)
+    if((c & 0b11000000) == 0b10000000)
         throw new std::invalid_argument("Unexpected UTF-8 continuation byte");
-    
+
     return 1;
 }