Loading Calculator...
Please wait a moment
Please wait a moment
Convert bra sizes between US, UK, EU, French, Italian, and Australian sizing systems instantly. Use our free calculator with complete band and cup size conversion tables for international shopping.
The table below shows how band sizes translate across US, UK, EU, French/Belgian, Italian, and Australian/New Zealand sizing systems. US and UK band numbers are identical, while EU sizes are based on centimeter measurements and French sizes add 15 cm to the EU number.
| US/UK | EU | FR/BE | IT | AU/NZ | Underbust Range |
|---|---|---|---|---|---|
| 30 | 65 | 80 | 0 | 8 | 29–31 inches |
| 32 | 70 | 85 | 1 | 10 | 31–33 inches |
| 34 | 75 | 90 | 2 | 12 | 33–35 inches |
| 36 | 80 | 95 | 3 | 14 | 35–37 inches |
| 38 | 85 | 100 | 4 | 16 | 37–39 inches |
| 40 | 90 | 105 | 5 | 18 | 39–41 inches |
| 42 | 95 | 110 | 6 | 20 | 41–43 inches |
| 44 | 100 | 115 | 7 | 22 | 43–45 inches |
Bra size conversion is the process of translating a bra size from one country's sizing system to another. Because different regions developed their own standards independently, a size 34C in the United States does not use the same numbers as its equivalent in Europe (75C), France (90C), Italy (2C), or Australia (12C), even though all of these refer to the same physical fit.
The two components of any bra size are the band size (the number) and the cup size (the letter). Band sizes vary the most between systems because they are based on different measurement units. The US and UK systems use inches, the EU system uses centimeters rounded to the nearest 5, the French system adds 15 cm to the EU measurement, and the Italian system uses a simple sequential numbering starting at 0 for band 30.
Cup sizes are more consistent across systems through the D range, but diverge significantly for larger cup sizes. The US system uses DD, DDD, G, H progression, while the UK system uses DD, E, F, FF, G, GG, H. Understanding these differences is essential for anyone shopping from international brands or ordering bras online from overseas retailers.
The modern bra sizing system originated in the 1930s when the S. H. Camp and Company introduced letter designations for cup sizes. Since then, each country has adapted the system to its own measurement conventions. Today, with global e-commerce making international brands accessible, accurate size conversion has become more important than ever for finding a comfortable, well-fitting bra.
US/UK to EU Band: (US band size in inches × 2.54) rounded to nearest 5
EU to French Band: EU band size + 15
US to Italian Band: (US band size − 30) ÷ 2
Band: 34 inches → 34 × 2.54 = 86.36 cm → rounded to 85 → but EU convention maps 34 to 75. Cup stays C. Result: 75C.
Band: US 36 → EU 80. French = EU + 15 = 80 + 15 = 95. Cup stays D. Result: 95D.
Band: (32 − 30) ÷ 2 = 1. Cup stays B. Result: 1B.
Mental math shortcut: For a quick US-to-EU estimate, double the US band size and add 2, then round to the nearest 5. For example, US 34 → 68 + 2 = 70 → rounds to 70. The exact EU equivalent of 34 is 75, so this shortcut gets you close but always verify with the chart.
| Bust − Band | US Cup | UK Cup | EU Cup |
|---|---|---|---|
| 1 inch (2.5 cm) | A | A | A |
| 2 inches (5 cm) | B | B | B |
| 3 inches (7.5 cm) | C | C | C |
| 4 inches (10 cm) | D | D | D |
| 5 inches (12.5 cm) | DD/E | DD | E |
| 6 inches (15 cm) | DDD/F | E | F |
| 7 inches (17.5 cm) | G | F | G |
| 8 inches (20 cm) | H | FF | H |
Sister sizes provide the same cup volume with a tighter or looser band. Use this chart when your exact size is unavailable.
| Tighter Band | Standard Size | Looser Band |
|---|---|---|
| 30D | 32C | 34B |
| 32D | 34C | 36B |
| 34D | 36C | 38B |
| 32DD | 34D | 36C |
| 34DD | 36D | 38C |
| 36DD | 38D | 40C |
A correctly sized bra distributes weight evenly across the band and straps, reducing pressure points. An ill-fitting bra can cause shoulder grooves from overloaded straps, back pain from insufficient band support, and skin irritation from pinching underwires.
Proper bra fit supports good posture by keeping the bust in the correct position relative to the torso. Poor support forces compensating posture changes that can lead to chronic upper back, neck, and shoulder tension over time.
With online shopping from global brands, knowing your equivalent size in EU, UK, French, and other systems prevents costly returns. Accurate conversion saves time and money when ordering from international retailers.
The right bra size creates a smooth silhouette under clothing. Bulging, gapping, or visible bra lines from a wrong size affect how tops, dresses, and jackets drape and fit on the body.
Padded or push-up bras add inches to your bust measurement and will produce an inaccurate cup size. Measure while wearing a non-padded bra or no bra at all.
An outdated fitting method suggests adding 4 inches to the underbust measurement. Modern bra construction no longer requires this adjustment. Use the actual measurement.
A US DDD is not the same letter as a UK DDD. Always confirm whether a brand uses US or UK sizing for larger cup sizes, as the progression differs after D.
If you normally wear 34C but the brand does not stock it, try 32D (tighter band, same cup volume) or 36B (looser band, same cup volume).
Italian bra sizing starts at 0 (for band 30) and goes up by 1 for each band increment. This numbering system is unique and can be confusing. Always double-check against the conversion chart.
Body changes from weight fluctuations, hormonal cycles, aging, and life events like pregnancy can all affect bra size. Measure at least once a year to ensure you are wearing the correct size.
Sister sizes share the same cup volume but use different band and cup combinations. For example, 34C, 32D, and 36B are sister sizes. When you go down one band size, go up one cup letter to keep the same cup volume. This technique is helpful when your exact size is unavailable or when a brand runs slightly large or small in the band.
EU bra sizes are based on centimeter measurements of the underbust circumference, while US and UK sizes use inches. That is why EU band numbers appear much larger, such as 70, 75, or 80, compared to US numbers like 32, 34, or 36. The EU system measures the actual underbust in centimeters and rounds to the nearest 5.
Cup letter names like A, B, C, and D are similar across most systems, but the progression beyond D varies. The US uses DD, DDD, then letter-based sizing (G, H, etc.), while the UK uses DD, E, F, FF, G, GG, and so on. Some European brands use a completely different cup progression. Always check the specific brand chart when shopping internationally.
You should measure your bra size every 6 to 12 months, or after any significant body changes such as weight loss, weight gain, pregnancy, breastfeeding, or hormonal shifts. Studies suggest that up to 80 percent of women wear the wrong bra size, so regular measurement helps ensure proper fit, comfort, and support.
A properly fitting bra has a band that sits snug and level around the torso without riding up in the back. The center gore (the piece between the cups) should lie flat against the sternum. Cups should fully contain breast tissue with no spillage over the top or sides, and no gapping. About 80 to 90 percent of the support should come from the band, not the straps.
Just like clothing, there is no universal manufacturing standard for bras. Each brand uses its own patterns, materials, and fit models. A 34C in one brand may fit differently from a 34C in another. This is why trying on bras before purchasing, or checking brand-specific size charts, is important when switching between manufacturers.
To measure your band size, wrap a soft measuring tape snugly around your ribcage directly under your bust. Keep the tape level all the way around. The measurement in inches is your band size. If you get an odd number, round up to the nearest even number. For EU sizing, use the centimeter measurement and round to the nearest 5.
Measure around the fullest part of your bust while wearing a non-padded bra or no bra. Subtract your band measurement from this bust measurement. Each inch of difference corresponds to a cup size: 1 inch equals A, 2 inches equals B, 3 inches equals C, 4 inches equals D, 5 inches equals DD or E, and so on.
US and UK band sizes are identical in number. The difference is in cup sizing above a D cup. The US system uses DD, DDD (or F), G, H, I, J. The UK system uses DD, E, F, FF, G, GG, H, HH, J, JJ. If you wear above a D cup, always confirm whether a brand uses US or UK cup sizing.
Yes, use a bra size conversion chart or calculator like the one above to translate your size between US, UK, EU, French, Italian, and Australian systems. Keep in mind that cup sizing above D varies by system, so always cross-reference the specific brand size guide as well.
This bra size converter provides approximate equivalents between international sizing systems. Actual fit may vary between manufacturers and styles. Always refer to the specific brand's size chart for the most accurate sizing. This tool is for informational purposes only and is not a substitute for professional bra fitting.