The relationship between cup size and the circumference on a bra is confusing to a lot of people. How does one know your cup size? Can you upgrade or degrade your cup size any way you want? We will sort out the questions you have regarding cup sizes for you.
This is how cup sizes work on your bra
You are not your cup size. How often have you heard “I am a C-cup” or “She is a B-cup”? If you disregard the absurdity of how you define your body (or in a worst-case scenario, your self worth) after the size of your bust, these quotes also contain pure inaccuracies.
By only referring to cup size without mentioning the band circumference, you are really not saying anything at all. In fact, there is a great difference between a C-cup and another C-cup, depending on your width around your torso.
In the picture below you can see two bras with different band sizes, but both are B-cups. The top one is size 95B and the bottom one is 65B. The volume is substantially different, the 65B is considerably smaller.
The volume of a cup lessens or expands depending on the band size you have. If you are 95cm under your bust and have a B-cup, then your breasts have the same volume as someone who measures 75cm under the bust, but sports an F-cup. However, the person with 75F will appear to have a larger bust when one is regarding the person in question. This is because the cup is more proportional compared to the rest of the bra. A person who has a wider back but a smaller bust, will automatically have “wider” breasts compared to a person who has a narrower back. In the picture below you can see Laila bra with different cup sizes. The top bra is a B-cup size 90, and at the bottom is an E-cup size 75. Both of these bras have the same volume in the cup.
The relationship between the cup and the band circumference
In the chart below the fields with gold marked cup sizes are equally large in volume compared to each other. If you usually wear 85C but after a while feel that it is too loose around your back because it has lost its elasticity, you could try and buy a size 80B instead. The cup of an 80D will still be as large as your old bra, but the bra will fit better to your body since it will feel more snug around your back.
Remember that the bra should sit tight while trying it on in the store. It will expand over time. It is like when you tried on your favorite jeans the first time, they were not as comfortable then as they are now. Most bras have elastane or lycra in their wings and will therefor expand and adjust after your body. That process of adjusting to your body shape will take approximately two weeks. More information about how the cup and the bra should fit your body can be found in our fitting guide.