One Stop Button Shop — Sewing buttons as a | onestopbuttonshop.com
Every common button size from 16L to 60L, converted to millimetres and inches, with the garment each band suits.
Button sizes are sold in lignes, and the conversion is fixed: 1 ligne equals 0.635 mm, exactly 1/40 of an inch. Multiply the ligne number by 0.635 for millimetres; divide millimetres by 0.635 to go back.
The anchor conversions worth memorising are 18L = 11.4 mm, 36L = 22.9 mm and 60L = 38.1 mm. Most replacement questions land on or between these three points.
Size bands map to garments. 16L-18L (10-11 mm) covers cuffs and children's wear; 24L-32L (15-20 mm) covers cardigans; 36L-60L (23-38 mm) covers coats. A standard 4-hole dress-shirt front button, 11-15 mm across, sits at roughly 18L-24L.
On narrow screens, swipe or scroll the plate sideways.
Coat and blazer buttons run 25-40 mm in diameter, which converts to roughly 40L-63L; within the trade bands, coats are quoted as 36L-60L. Jeans and workwear jackets sit outside the sew-on scale entirely, using tack buttons with a cap of about 17-20 mm.
If you measured a button in millimetres, divide by 0.635 and round to the nearest even ligne number, because that is how sizes are stocked. A 12 mm shirt button works out to about 19L, so 18L or 20L is the practical ask.
For the hole and spacing that go with each size, see the buttonhole and spacing guide; for the attachment each fabric needs, see the button types guide. The homepage answers the sizing question end to end.
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