The buttonhole is not centered over the button; it is back off from the center front. Specifically: the buttonhole start 1/8″ (3 mm) from the button (toward “Left-hand Side (as worn)”). the rest of the buttonhole is at the right-hand side (as worn) of the button.

Where should buttonholes be placed?

Horizontal buttonholes should extend 1/8 inch over the center front or back toward the garment edge. Vertical buttonholes should be sewn on the center front or back lines and are best for garments with a banded or placket opening. Generally, this type of buttonhole is found on blouses or shirts.

How far should buttons be from the edge?

The button center should be one button's width away from the front edge. So if you're using a 1/2” wide button, your marks will be 1/2” from the front edge. The center of the top button should be 1/4” + half a button's width from the top edge.