diff --git a/src/indent_helper.hpp b/src/indent_helper.hpp
index fcc8ad0..e009ee0 100644
--- a/src/indent_helper.hpp
+++ b/src/indent_helper.hpp
@@ -7,6 +7,8 @@ enum class IndentAction
     None
 };
 
+constexpr int TAB_WIDTH = 8;
+
 class IndentHelper
 {
     std::stack<int> indent_stack;
@@ -56,4 +58,14 @@ public:
         pending_dedents--;
         return true;
     }
+
+    static int calculateColumn(const char *text, int length)
+    {
+        int spaces = 0;
+        for (int i = 0; i < length; i++)
+        {
+            spaces += (text[i] == '\t') ? TAB_WIDTH : 1;
+        }
+        return spaces;
+    }
 };
\ No newline at end of file
diff --git a/src/lexer.l b/src/lexer.l
index 3ec588b..b603b70 100644
--- a/src/lexer.l
+++ b/src/lexer.l
@@ -14,15 +14,14 @@
 ^[ \t]*#.*\n   { /* Ignore comment-only lines */ }
 
 ^[ \t]* {
-    int spaces = 0;
-    for (int i = 0; i < yyleng; i++)
-        spaces += (yytext[i] == '\t') ? 8 : 1;
+    int col = indent_helper.calculateColumn(yytext, yyleng);
+    auto action = indent_helper.processLine(col);
 
-    IndentAction result = indent_helper.processLine(spaces);
-    if (result == IndentAction::Indent) return yy::parser::token::TOK_INDENT;
-    if (result == IndentAction::Dedent) return yy::parser::token::TOK_DEDENT;
+    if (action == IndentAction::Indent) return yy::parser::token::TOK_INDENT;
+    if (action == IndentAction::Dedent) return yy::parser::token::TOK_DEDENT;
 }
 
+
 \n       { return yy::parser::token::TOK_NEWLINE; }
 
 def      { return yy::parser::token::TOK_KW_DEF; }