Excel for Mac uses standard measurement units, such as inches and pixels, to establish column widths, row heights, and the graduations of the horizontal and vertical sheet rulers.
You can change the default units for the rulers.
Note: If you don't see the rulers on your sheet, on the View menu, click Page Layout, and then click Ruler.
On the Excel menu, click Preferences.
Under Authoring, click General .
On the Ruler units menu, click the unit of measurement that you want to use.
Tip: You can also see the column width by dragging the column separator on the sheet and observing the ScreenTips as you drag.