This brings you back to your Excel spreadsheet, and the column widths will adjust automatically as soon as you reactivate the sheet (by selecting any cell).

Click "Default Width" under the Cell Size heading. Insert your desired column width into the box labeled "Standard column width." Your spreadsheet now features one set column width for all columns.

You can lock the position of a chart in Excel spreadsheet so that it doesn't move or resize when you include more columns and change cell width. Learn how!