File Extension HCX File Format ChartXL Chart HCX stands for ChartXL Chart. This was last updated in March 2012 By Margaret Rouse Browse File Extensions Alphabetically: A B C D E F G H I J K L M N O P Q R S T U V W X Y Z # Ask a Question. Find an Answer. Ask your peers a question about this file extension. Ask a Question Building a Library of Routines - Setup_PivotChart Pivots and Charts Want a Free Gantt Chart App?