The default width of an Excel column is 8.43 characters, but you can adjust each individual column from 0 to 255 characters wide.
Position the mouse pointer to the right of the column you want to adjust. The mouse pointer becomes a crosshair.
Press and hold the mouse button, and drag the column line to the right to increase the column width or to the left to decrease it.
Release the mouse button. The column width will be changed.
Tip
Adjust Columns Automatically To automatically adjust column width to exactly fit the contents of the cell, double-click the mouse after the pointer becomes a crosshair.