AlienStar, This is how you can get the maximum font size to fit in a label: #include <GUIConstantsEx.au3> #include <StaticConstants.au3> #include <FontConstants.au3> #include "StringSize.au3" #include <Array.au3> $hGUI = GUICreate("Example", 1072, 330) $cLabel = GUICtrlCreateLabel("", 15, 15, 1072 - 30, 330 - 30, $SS_CENTER + $SS_SUNKEN) GUICtrlSetBkColor($cLabel, 0xC4C4C4) GUISetState(@SW