Find the correct zipper length for any sewing project based on opening size, zipper type, and application.
Opening Measurement
Measure the actual opening the zipper needs to span, not the garment seam length.
Zipper Type
Centered zippers sit in the middle of a seam with equal fabric on each side.
Invisible zippers are sewn differently and typically need to be 1-2 inches longer than the opening.
#3 for lingerie and light garments. #5 for most clothing and bags. #8-10 for heavy bags and outerwear.