Change Weekday Abbreviations in Tableau Week day abbreviations using either three-letter abbreviations (Jan, Feb, Mar, etc.) or one-letter abbreviations (for example, M, T, W, etc.) How to display month or week day abbreviations using either three-letter abbreviations ( Jan, Feb, Mar, etc.) or one-letter abbreviations (for example, M, T, W , etc.). Follow the steps below: Drag the Date dimension (as a discrete field) to the view and choose Month or Weekday . Right-click the date dimension or the header in the view and select Format . In the Header section, select Abbreviation or First Letter in the "Date" menu.