Global Size Converter
Shopping from another country? A size is only a label in one system. The Global Size Converter translates any size you already wear into all seven systems this site covers — US, UK, EU, French, Australian, Japanese and Indian — using the same math as the main calculator, so the results always agree.
Convert Your Size
Sizes on this page are estimates. Sizing varies by brand and style, so always check the brand’s own size chart and try on before you buy. Nothing here is medical advice.
How conversion works
Conversion reads your size as a body, then re-labels it. Your band number becomes an underbust measurement (inches or centimetres, depending on the system), and your cup letter becomes a bust-to-band difference. Each target system then applies its own band rule — US, UK and Indian bands round the underbust to the nearest even inch; EU, French and Japanese bands round centimetres to the nearest 5; French bands add 15 to the EU number; Australian bands subtract 22 from the inch band — and its own cup-letter progression.
Worked example: a US 34C is a 34-inch underbust with a 3-inch difference. In UK sizing that is still 34C. In EU sizing the band rounds to 85 cm and the third cup letter is D, giving 85D. In French sizing the band adds 15, giving 100D. In Australian sizing the band subtracts 22, giving 12C. In Japanese sizing it is 85D, and in Indian sizing 34C. One body, seven labels.
The 7 systems at a glance
| System | Band rule | Cup letters | Used for |
|---|---|---|---|
| US | Inches, nearest even (28–48) | AA–K, with DD and DDD | US brands and many international brands |
| UK | Inches, nearest even (28–48) | AA–JJ, with DD, FF, GG, HH, JJ | UK brands such as Panache, Freya, Elomi |
| EU | Centimetres, nearest 5 (60–110) | A–H, consecutive | Most of continental Europe, Brazil |
| FR | EU centimetres + 15 (75–125) | A–H, consecutive | French brands such as Chantelle |
| AU | US inches minus 22 (6–26) | AA–JJ, like UK | Australian and New Zealand brands |
| JP | Centimetres, nearest 5 (60–110) | A–K, consecutive | Japanese brands; very close to Korean sizing |
| IN | Inches, nearest even (28–48) | AA–JJ, like UK | Indian brands and UK-style imports |
Why conversions sometimes disagree
Three reasons. Rounding: some charts convert bands by direct unit math (34 inches = 86.36 cm) while systems round (nearest even inch, nearest 5 cm) — the rounded value is the one brands actually sell. Letter progressions: an EU E is not a UK E, because the UK inserts doubled letters that the EU skips; a letter only means something inside its own system. Brand grading: brands scale patterns differently, so two brands in the same system can still fit differently. When charts disagree, trust the one that follows the system's own rounding — and then check the brand's own chart.
The cup-letter traps
Three traps catch almost everyone. First, the EU E: an EU E is not a UK E. The UK inserts doubled letters, so a UK E is roughly a US DDD, while an EU E is roughly a US DD — different volumes behind the same letter. Second, the Japanese climb: Japanese and Korean cup letters rise in 2.5 cm steps instead of one-inch steps, so a US DD becomes a Japanese F or G. The letter looks dramatic; the volume is not. Third, the Australian shortcut: Australian cup letters match the UK progression, so a UK size and an Australian size with the same cup letter are close — but the band numbers differ by 22, so never copy the band across.
The safe habit is to convert the whole size, band and cup together, every time — and to distrust any chart that converts only the band or only the cup.
Frequently Asked Questions
Why is my EU size a different letter from my UK size?
Because the two systems assign letters differently as sizes increase. UK sizing inserts doubled letters (DD, FF, GG), while EU sizing uses consecutive letters (D, E, F, G). A US 34C converts to an EU 85D, not an 85C — the letter shifts because the EU band is in centimetres and its cup steps are counted differently.
Is a US DDD the same as a UK E?
Usually, yes. The UK progression after DD is E, F, FF, G, GG, while the US progression after DD is DDD, G, H. So a US DDD normally converts to a UK E, and a US G to a UK F. The converter uses exactly this mapping.
Why do Japanese sizes look so much bigger?
Japanese and Korean cup letters climb faster than US ones: a US DD is commonly labeled F or G in Japan for the same volume. The bands are in centimetres too (a US 34 is roughly a Japanese 75). A Japanese 75F is not a huge size — it is roughly a US 34DD in different clothes.
Can I convert from a size I only know in one system?
Yes — that is what this tool is for. Enter the size you already wear and its system, and the converter shows every equivalent. If you do not know your size in any system yet, measure first with the main calculator.
Why do two conversion charts disagree?
Because charts round differently. Some charts convert the band by direct unit conversion, others by the sizing system's own rounding rule (nearest even inch, nearest 5 cm). This converter follows the same rounding rules as this site's calculator, so its results always match the calculator.
What if my converted cup is beyond a system's range?
EU, French and Japanese lists top out at H on this site. If your difference is larger, the converter clamps to the largest letter and notes it. In that case, check the brand's own chart — some brands extend further than the standard lists.