Bra size reference tables
Triumph subset: EU bands 65–100 and cups A–F; A is not listed for bands 95–100. Whole-centimetre underbust lookup, with 0.5 cm rounded up. Bust intervals include both ends, so boundary values can match two cups.
JP follows Triumph’s international label chart, not a Japanese measurement calculation. JP is unavailable for band 65, A above band 80 and 100D. — means unavailable.
Underbust and band labels
| Underbust (cm) | EU | UK | US | France | JP |
|---|---|---|---|---|---|
| 63–67 | 65 | 30 | 30 | 80 | — |
| 68–72 | 70 | 32 | 32 | 85 | 70 |
| 73–77 | 75 | 34 | 34 | 90 | 75 |
| 78–82 | 80 | 36 | 36 | 95 | 80 |
| 83–87 | 85 | 38 | 38 | 100 | 85 |
| 88–92 | 90 | 40 | 40 | 105 | 90 |
| 93–97 | 95 | 42 | 42 | 110 | 95 |
| 98–102 | 100 | 44 | 44 | 115 | 100 |
Bust circumference (cm) by EU band and cup
| EU band | A | B | C | D | E | F |
|---|---|---|---|---|---|---|
| 65 | 77–79 | 79–81 | 81–83 | 83–85 | 85–87 | 87–89 |
| 70 | 82–84 | 84–86 | 86–88 | 88–90 | 90–92 | 92–94 |
| 75 | 87–89 | 89–91 | 91–93 | 93–95 | 95–97 | 97–99 |
| 80 | 92–94 | 94–96 | 96–98 | 98–100 | 100–102 | 102–104 |
| 85 | 97–99 | 99–101 | 101–103 | 103–105 | 105–107 | 107–109 |
| 90 | 102–104 | 104–106 | 106–108 | 108–110 | 110–112 | 112–114 |
| 95 | — | 109–111 | 111–113 | 113–115 | 115–117 | 117–119 |
| 100 | — | 114–116 | 116–118 | 118–120 | 120–122 | 122–124 |
Cup label correspondence
| EU | UK | US | France | JP |
|---|---|---|---|---|
| A | A | A | A | B |
| B | B | B | B | B/C |
| C | C | C | C | C |
| D | D | D | D | D |
| E | DD | DD | E | DD |
| F | E | DDD | F | E |
How to use this bra size calculator
Choose centimetres or inches before entering two measurements. Measure around the ribcage directly below the bust for A, then around the fullest part for B. Select the region in which you want to read the first result and choose Find bra size. The result includes the other supported regional labels, while the corresponding band and cup rows are highlighted below.
The initial example is ready to calculate. If you focus an example field, the faint value disappears so you can type. An empty field restores its example when you leave it, without restoring a result. Editing measurements clears the previous answer and disables Copy. Changing units converts valid measurements, keeping the physical dimensions; calculate again to confirm.
Measuring for a useful starting point
Use a flexible tape and a mirror or another person's help to keep it horizontal around your back. Take the underbust measurement firmly below the bust and the bust measurement loosely at the fullest part, with arms relaxed. A diagonal tape or one that slips upward measures a different path. The drawing identifies the two levels without judging body shape.
Write down the two values and their unit together. Do not enter the number printed on a current bra as an underbust measurement: a band label and a measured circumference are different things. This is a two-measurement chart lookup; it does not collect photos, assess health or determine an ideal body size.
How the chart lookup works
The calculator uses a stated subset of Triumph's chart, not a universal equation for every bra. It converts inches using 1 in = 2.54 cm and rounds underbust to the nearest whole centimetre, with halves up. That rounded value chooses a band interval. The unrounded bust measurement is then compared with the published bust intervals in that band's column.
Supported labels are EU bands 65–100 and EU cups A–F. The A cells for bands 95 and 100 are absent in the reference and remain unavailable here. Cup interval endpoints overlap: at an exact shared endpoint, both candidates are shown. No missing size is extrapolated. Regional labels follow this source's correspondence and may differ from another brand's lettering.
Two examples to check
With 75 cm underbust and 90 cm bust, the matching result is EU 75B, UK 34B, US 34B and France 90B. Choosing France changes which label is prominent, not the underlying measurements.
With 80 cm underbust and 101 cm bust, the result is EU 80E, UK 36DD, US 36DD and France 95E. By contrast, 75 cm and 91 cm sit on the B/C boundary, so both 75B and 75C appear. Those candidates describe a chart boundary, not two guaranteed fits.
Why is this different from another calculator?
Calculators can use different measuring positions, band rules and cup progressions. Compare the named method before comparing just the final label. This page deliberately keeps one chart consistent instead of mixing one brand's band rule with another brand's cup formula. It is not affiliated with Triumph.
Does a cup letter describe a fixed volume?
No. Read a cup letter together with its band label. This tool does not compute breast volume or recommend a sister size. The regional tables translate this reference's labels; they are not a measurement of the garment's construction.
What should I do with no match?
Check that the unit is correct and that A and B were not swapped. Enter decimals as 75.5 or 75,5, without thousands separators or fractions. If the measurements still fall outside this subset, consult the full manufacturer chart or a fitting service. A no-match message means the table cannot answer, not that your measurements or body are wrong.
Will the result fit every style?
No. Use the size as a starting point for comparing a specific product and its fitting guidance. The calculator cannot test support, comfort or how a garment sits while moving. Keep the chart name when copying the result, and follow the product's own guidance if it uses a different sizing system.