Wrap the tape directly under the bust where the band sits. Keep it snug and level all the way around.
This anchors the band size in most systems.Best for comparing cup letter systems after a band size is already known.
Cup Size Chart
Use a cup size chart to understand how bust-to-underbust difference maps to common cup labels across regional systems.
Measure and get a size suggestion
Use your own measurements to find the closest reference row, then confirm with the brand chart.
How to measure
Bra- Measure underbust level and snug.
- Measure bust at the fullest point.
- Use the difference for cup reference, then check the brand method.
Your measurements
Closest reference
Enter the measurements you have. A partial result is okay, but more fields give a better match.
Reference only. Product cut, ease, width, material, and brand rules can change the final size.Measurement details
Use a soft tape and a non-padded or lightly padded bra. Keep the tape level and breathe normally.
Measure around the fullest part of the bust without flattening the tissue.
A mirror helps keep the tape from dipping in the back.Use the difference between bust and underbust as the cup reference, then check the regional cup system.
Cup letters are not absolute volumes by themselves.The band should support, cups should not gap or spill, and straps should not carry all the weight.
Sister sizing can help when the band fits but cup volume feels off.| Difference | Difference (cm) | US cup | UK cup | EU cup |
|---|---|---|---|---|
| 1 in | 2.5 cm | A | A | A |
| 2 in | 5 cm | B | B | B |
| 3 in | 7.5 cm | C | C | C |
| 4 in | 10 cm | D | D | D |
| 5 in | 12.5 cm | DD/E | DD | E |
| 6 in | 15 cm | DDD/F | E | F |
| 7 in | 17.5 cm | G | F | G |
| 8 in | 20 cm | H | FF | H |
| 9 in | 22.5 cm | I | G | I |
| 10 in | 25 cm | J | GG | J |
| 11 in | 27.5 cm | K | H | K |
| 12 in | 30 cm | L | HH | L |
| 13 in | 32.5 cm | M | J | M |
| 14 in | 35 cm | N | JJ | N |
Cup Size Starts With a Difference
Cup references usually begin with the difference between the bust measurement and the underbust or band measurement. This difference is then mapped to a cup label. Because brands calculate and round measurements differently, the chart should be used as a practical reference, not a universal formula.
US, UK, and EU Cup Labels
Cup labels are especially confusing after D because regions and brands do not always progress in the same way. A US DD/E may not match a UK E on every product page. Check the retailer's sizing notes and compare the full band plus cup combination before ordering.
Why Cup Letters Are Not Standalone
A cup letter depends on band size. For example, two sizes with the same cup letter can fit differently because the band changes the overall volume. If you are comparing products or sister sizes, always keep the band label visible alongside the cup label.
Professional Fit Language
This chart focuses on measurement mechanics and shopping reference. It avoids claims about body type and does not replace a professional fitting when comfort, support, or health-related concerns matter. For specialty products, use the brand's exact measurement method.
Why Cup Progression Differs by Region
Cup labels after D vary across US, UK, and EU systems. Some US charts use DD/E and DDD/F, while UK charts often progress through DD, E, F, FF, G, and GG. That means a cup conversion should be treated as a regional label reference, not a universal formula. The safest display keeps the band and cup together and explains the difference measurement behind the letter.
Using Cup Charts Without Overpromising
A cup chart is helpful for understanding measurement difference, but it cannot guarantee comfort. Breast shape, wire width, cup height, fabric stretch, and brand grading all influence the final fit. The page should avoid medical language and avoid promising a perfect result. Its real value is helping shoppers read brand charts more confidently and understand why the same letter can feel different across products.
Related Size Tools
Continue with closely related tools instead of jumping through an unrelated directory.
Bra Size Chart
Best for understanding how band and cup references work together.
Clothing Size Chart
Best for explaining the difference between body measurements and apparel labels.
Size Chart Generator
Best for merchants who need a product-page size chart quickly.
Shoe Size Chart
Best for using measured foot length as the anchor for international shoe sizes.
FAQ
What measurement is used for cup size?
Cup charts commonly use the difference between bust and underbust or band measurements.
Are DD and E the same cup size?
They can overlap in some systems, but regions and brands label cup progression differently.
Can I use cup size without band size?
No. Cup labels depend on band size and should be read together.
Is this cup size chart exact for every brand?
Use the result as a sizing reference, then check the brand or seller chart before buying. Materials, fit preference, country labels, and manufacturing tolerances can change the best choice.