Button Size Guide: Ligne, Millimetres and How to Pick the Right Size
Ask a buyer why a bulk button order went wrong, and the answer is often simple: the size was wrong. Maybe the button was too big for the buttonhole, too small to look balanced, or specified in one unit by the designer and read in another by the supplier. Size mix-ups are among the most avoidable trim errors, and they are expensive because they usually surface after thousands of pieces are already made. This guide explains how button sizing works, gives a conversion chart, and shows how to choose and specify the right size for different garments. What Is a Ligne? Button sizes in the garment trade are commonly given in ligne (often written as L), a unit that comes from the French button-making tradition. One ligne equals one fortieth of an inch, which is about 0.635 mm. The larger the ligne number, the larger the button. Many suppliers and factories still use ligne as the everyday standard, while designers and tech packs often use millimetres or inches. Knowing both avoids conf...