👙 US Bra Size to FR Bra Size Converter
Free online tool to convert US bra sizes to FR. Enter your band and cup size for an instant, accurate result — band and cup both converted.
Result
90C
34C US = 90C FR
US Bra Size to FR Bra Size Conversion Table
| US Size | FR Size |
|---|---|
| 30A US | 80A FR |
| 30B US | 80B FR |
| 30C US | 80C FR |
| 30D US | 80D FR |
| 30DD US | 80DD FR |
| 30DDD US | 80E FR |
| 32A US | 85A FR |
| 32B US | 85B FR |
| 32C US | 85C FR |
| 32D US | 85D FR |
| 32DD US | 85DD FR |
| 32DDD US | 85E FR |
| 34A US | 90A FR |
| 34B US | 90B FR |
| 34C US | 90C FR |
| 34D US | 90D FR |
| 34DD US | 90DD FR |
| 34DDD US | 90E FR |
| 36A US | 95A FR |
| 36B US | 95B FR |
| 36C US | 95C FR |
| 36D US | 95D FR |
| 36DD US | 95DD FR |
| 36DDD US | 95E FR |
Conversion Formula
Band conversion reference: US/UK: 28 30 32 34 36 38 40 42 44 EU: 60 65 70 75 80 85 90 95 100 FR: 75 80 85 90 95 100 105 110 115 AU: 6 8 10 12 14 16 18 20 22 JP/RU/KR: same as EU Cup conversion — canonical index (12 sizes, index 0–11): US: AA A B C D DD DDD G H I J K UK/AU/FR: AA A B C D DD E F FF G GG H EU/JP/RU/KR: AA A B C D E F G H I J K Common mistakes: US DDD ≠ UK DDD — US DDD = UK E US G ≠ EU G — US G = EU G (index 7 matches here) US DD = UK DD (same), but US DD = EU E (different)
About US Bra Size to FR Bra Size Conversions
Converting bra sizes from US to FR requires converting both the band number and the cup letter. Enter your size above to get the correct FR equivalent with cup conversion included.
This conversion uses a non-linear (reciprocal) relationship, so a simple multiplication factor does not apply. The formula section below explains the method, and the reference table shows common converted values.
For reference: this page provides a US-to-FR conversion table covering common values, the exact mathematical formula, and frequently asked questions.
Frequently Asked Questions
How do I convert US Bra Size to FR Bra Size?
This conversion is non-linear. Use the calculator above for accurate results, or refer to the formula section on this page.
How many FR Bra Size are in 1 US Bra Size?
The relationship between US Bra Size and FR Bra Size is non-linear. Use the calculator above or the reference table on this page for specific values.
Is US Bra Size larger or smaller than FR Bra Size?
The size relationship between US Bra Size and FR Bra Size depends on the input value because this conversion is non-linear (reciprocal).
When would I use FR Bra Size instead of US Bra Size?
Use FR sizing when shopping brands that label their products in the FR system — for example, European luxury brands, UK high street stores, or Japanese lingerie retailers. Always verify sizing with the brand's own chart, as fit can vary by style and manufacturer even within the same system.
Why doesn't my cup letter stay the same when converting between systems?
Cup letters are only consistent up to D cup. From DD upward, the US uses DD, DDD, G, H, I while UK and AU use DD, E, F, FF, G, GG, H, and EU uses E, F, G, H, I. This means US 34DDD = UK 34E = EU 75F. The band number also changes because each system uses a different scale — US in even inches, EU and JP in 5 cm increments, FR adds 15 to the EU number, and AU uses garment numbers.
What is the most common conversion mistake with international bra sizes?
The most common mistakes are (1) keeping the cup letter unchanged when it should change — US DDD is NOT UK DDD, it is UK E; and (2) only converting the band while ignoring the cup. Both band and cup must be converted for an accurate size. A second common mistake is confusing EU and FR sizing: FR sizes are EU + 15 in the band but use the same cup letters.
Related Bra Size Conversions
All conversion results are provided for general informational purposes only. Our formulas use internationally recognized conversion factors; however, rounding may affect precision. Do not rely on these results for professional, medical, legal, or engineering decisions without independent verification. Read our full disclaimer.