You will need
  • - the tape
  • assistant or mirror
Undress completely or to the Laundry to reduce the measurement error. Any clothing will add extra mm will make a mistake in what is a not too precise measurement.
It is better to ask someone to help you, or at least to control the process of measuring, looking in the mirror.
Wrap yourself with measuring tape under the breast, trying to place the tape parallel to the floor. Be careful that the tape is straight and parallel to the floor at the back. Write down the resulting number.
Wrap the tape around them so that centimeter passed on to the teats, keep behind the tape was parallel to the floor. The tape should hold well on the body, but not to compress the chest. Write down this number.
To determine Cup size bra subtract the second result of the first. If the difference is less than 10cm, the Cup size will be A. If the difference is 10-15cm - the size of B. the Difference from 15 to 17cm is the size C. To 20 cm - the size of D. Sometimes the size of the Cup indicate with numbers: 1, 2, 3, etc.
Now you can easily navigate in a lingerie store is knowing your chest circumference (the measurement result in step 2) and the value of the Cup (we defined it in step 4). The size is usually written as 70A, 75B. The first figure is the volume of the chest, the second is the Cup size of the bra.