Cherry SizeMethod and limits
How the Cherry Size calculator turns two measurements into a size estimate, where its tables come from, and what it cannot tell you.
How the estimate is calculated
- You enter two measurements, in centimetres or inches: the underbust (tape snug, just under the breasts, level all round) and the bust (tape loose, over the fullest part).
- Band: the underbust is rounded to the nearest 5 cm, from 60 to 110 cm, then written in each system's numbering: the same number in EU, Korean and Japanese sizing, 15 more in French sizing, and a numbering of their own in UK and US sizing (EU 75 = 34), which is not the underbust in inches.
- Cup: the difference between bust and underbust. About 10 cm gives an A, then every 2.5 cm (about an inch) adds a cup: B ≈ 12.5 cm, C ≈ 15 cm, D ≈ 17.5 cm. The difference is rounded to the nearest cup.
- That cup is then written with each system's letters: the UK doubles some letters (DD, FF, GG), the US continues with DDD and DDDD, and Japan writes the cup before the band (C70).
- The website calculator runs in your browser: your measurements are not sent to us.
Limits
- It is an estimate, not a fitting. Near the edge between two bands or two cups, a centimetre more or less changes the result, so both sizes are worth trying.
- Sizes vary between brands, and between models of the same brand: cut, fabric, underwire and padding all change how one label fits. Treat the result as a starting point and try its sister sizes too.
- Conventions differ. Some European brands count about 2 cm per cup, so they may label the same measurements up to one cup lower. Some calculators also use the underbust in inches directly as the band, which gives a different band number from ours.
- Italian and Brazilian sizes, and US letters beyond DD, vary most from brand to brand: treat those conversions as indicative.
Where the tables come from
These steps (one band per 5 cm of underbust; A at about 10 cm of difference, then 2.5 cm per cup) are the ones used in the size guides of several bra makers. For Japanese and Korean sizing we compared them with the guides listed below, which use the same steps. Conversions between systems (EU 75 = FR 90 = UK/US 34) follow the usual brand correspondences and remain indicative.
Who publishes this page
Cherry Size is published by PRO DIGITAL SERVICES SARL, Lausanne, Switzerland. This page is written and kept up to date by the publisher; it has not been reviewed by an outside bra-fitting expert.
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Your size, everywhere you shop
Cherry Size keeps your measurements on your iPhone, translates them into 617 brands, tracks changes through pregnancy, nursing or weight shifts (with a subscription) — and never uploads a thing. In the app, your size is free, and so is your size at 3 brands you choose. Every brand, the fitting room, the wardrobe and the journal need a subscription, with a free trial for eligible new subscribers.
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