1. To determine the cup, it is necessary to measure the upper and lower bust circumference respectively. The upper bust circumference is measured horizontally with a soft ruler at the nipple, and the lower bust circumference is measured horizontally with a soft ruler at the breast root. After measuring the upper and lower bust circumference, calculate the cup size with the difference between the upper and lower bust circumference.
 2. The cup size is determined by the difference between the upper bust and the lower bust. The difference between the upper bust and the lower bust is 10 cm, representing cup A, 12.5 cm, representing cup B, and 15 cm, representing cup C. The difference between the upper bust and the lower bust will increase by 2.5 cm for each additional cup.
 3. If you want to know the correct number of cups, you should accurately measure the size of the upper and lower chest circumference.
 4. If in the process of measuring the upper and lower chest girth, the size of the chest girth is uncertain and has decimals, then choose the next method. For example, if the measured size is 75.1cm, it will be counted as 76cm.
 5. When measuring the cup size, it is recommended to take off all the clothes and stand upright, with the upper body slightly tilted forward, so that the measured upper bust size is more accurate.
 6. If the chest sags or expands more seriously, when measuring the chest circumference, you should lift the chest to the middle with your hands, so that the measured chest circumference will be more accurate.
 7. If there is too much fat, the number of cups should be one size larger.