A bottle nipple size selection system for more accurately matching a bottle nipple to the individual anatomy of the mother. The bottle nipple size selection system generally includes a flat, rectangular member having a plurality of sizing apertures extending from its first end to its second end. Each of the apertures has a different diameter, wherein each of the aperture sizes are generally offset by at least 4 mm. By utilizing the apertures on the template, the mother may more accurately locate a bottle nipple which will match the size and contour of the mother's nipple to prevent the mother's baby from refusing breastfeeding due to becoming accustomed to a differently-sized bottle nipple.