Bra Size Conversion Table
Convert bra band and cup sizes between Taiwan, US/UK, Europe, and Japan sizing systems.
Includes measurement tips and sister-size examples so you can shop internationally with confidence and find the right fit every time.
Bra Size Conversion Table
Convert bra band and cup sizes between Taiwan, US/UK, Europe, and Japan sizing systems.
About this tool
Includes measurement tips and sister-size examples so you can shop internationally with confidence and find the right fit every time.
Unit
cm
cm
Filter by region
Underbust ranges are measured in centimeters. Taiwan often lists both the centimeter value (e.g. 70) and the related US/UK number (e.g. 32).
| Underbust range | US band |
|---|---|
| 58 - 62 cm | 28 |
| 63 - 67 cm | 30 |
| 68 - 72 cm | 32 |
| 73 - 77 cm | 34 |
| 78 - 82 cm | 36 |
| 83 - 87 cm | 38 |
| 88 - 92 cm | 40 |
| 93 - 97 cm | 42 |
| 98 - 102 cm | 44 |
| 103 - 107 cm | 46 |
| 108 - 112 cm | 48 |
| 113 - 117 cm | 50 |
| 118 - 122 cm | 52 |
When to use this conversion table
Bra sizing systems differ by region, so the same garment may carry several labels. This table cross-references band and cup notations across major markets to help you read a label or compare an online listing without confusion.
- Buying lingerie while travelling abroad and the store uses an unfamiliar numbering.
- Shopping from international e-commerce sites that only list local sizes.
- Picking a size for a friend or family member who lives in another country.
- Decoding a vintage or imported label that mixes inches, centimeters, and lettered cup grades.
How to measure bust and underbust
Keep a relaxed posture and measure on bare skin or with a thin, non-padded bra to reduce error.
- Stand naturally, relax shoulders, avoid holding your breath.
- Keep the tape level and snug to the body when circling underbust and bust points.
- Thin wireless or unpadded bras are fine; thick padding can distort numbers.
Cup difference basics
A cup generally changes every 2–2.5 cm (about 1 inch) of bust-underbust difference; values are approximate references.
- Taiwan/Japan often use 2.5 cm grading; some US/UK brands use 1-inch steps and name DD/DDD separately after D.
- Actual fullness and shape still depend on design; use the table as a quick guide then confirm by trying on.
Fit reminders & disclaimer
- Sizing varies by brand, country, fabric, and cup style; labels may mix centimeters and US/UK numbers.
- The chart is for general reference only; the best size is the one that fits comfortably when tried on.
Sister size examples
Sister sizes share a similar cup volume with a different band. Adjust band down, go up one cup letter; adjust band up, go down one cup letter.
75C ≈ 70D or 80B80D ≈ 75E or 85C70B ≈ 65C or 75A
Check band tension and strap adjustability when moving between sister sizes; comfort comes first.
FAQ
Common questions and answers about this topic.
Will weight changes affect bra size?
Weight changes usually move the underbust and bust together, so the difference (and therefore the cup letter) can shift. After a noticeable change of around 3 kg or more, re-measure both numbers and compare against the table again.
Should I pick the same size for wired and wireless bras?
The numerical band and cup are usually the same, but wireless designs rely more on band tension. Some brands suggest going one band tighter for the wireless version; let actual try-on stability decide.
How do I pick the right bra size when shopping online?
Re-measure your underbust and bust first, then convert the seller's regional label using this table. Keep a sister size as backup, and prefer sellers that publish actual garment measurements and accept exchanges.
Does this chart apply to sports bras and swimwear?
The underbust and cup logic is the same, but sports bras often use S/M/L tags and swimwear sometimes uses one-piece sizing. Treat this table as a baseline reference and always cross-check the brand's own size chart.
What is Bra Size Conversion Table?
Compare bra band sizes and cup measurements across Taiwan, US/UK, Europe, and Japan with optional filters.
Is Bra Size Conversion Table free to use?
Yes, Bra Size Conversion Table is completely free to use.