Turn on Options|Column Numbers to have EditPad display a horizontal ruler above the file indicating column numbers. Column numbers are only displayed when using a fixed-width font or a monospaced text layout.
Note that “column numbers” is a file type specific setting in EditPad Pro. If you change the setting through the Options menu or the toolbar, it is applied to the active file only. If you create a new file or open an existing one then EditPad uses the setting you made on the Editor page for the type of file you are creating or opening. Also, when you use File|Save As to save the file as a different file type, the setting for the current file changes to what you specified for the new file type.