using a measuring tape, measure your child’s wrist flush to the skin. add 1/2” to the wrist measurement and then order the closest size provided. (i.e. If baby’s wrist measures 3.5 - 3.75" you would order the 4.0” bracelet because all bracelets come with 3 extension loops to help you resize for a more accurate fit. If baby's wrist measures between 3.75 - 4.0" you should order the 4.5" bracelet to ensure longer use.)