diff --git a/lib/tokenize.cpp b/lib/tokenize.cpp
index 1a6b3d271..a87802cf8 100644
--- a/lib/tokenize.cpp
+++ b/lib/tokenize.cpp
@@ -2801,7 +2801,7 @@ bool Tokenizer::simplifySizeof()
                 if (size == 0)
                     continue;
 
-                sizeOfVar[varId] = size * static_cast<unsigned long>(MathLib::toLongNumber(tok->strAt(2)));
+                sizeOfVar[varId] = size * static_cast<unsigned int>(MathLib::toLongNumber(tok->strAt(2)));
             }
 
             else if (Token::Match(tok->previous(), "%type% %var% [ %num% ] [,)]") ||