Sizing in swimwear is less standardised than in ready-to-wear clothing, and the gap between Japanese, European, and US conventions is wide enough to cause real problems. If you have ever ordered swimwear from a Japanese brand and found it smaller than expected, or from a European brand and found it larger, the sizing system is usually the reason.
Japanese S/M/L versus European sizing ¶
Japanese ready-to-wear sizing runs approximately one size smaller than European sizing. A Japanese M corresponds roughly to a European S or a UK 8-10. In swimwear, the gap can be even larger because Japanese swimwear has historically been cut for a narrower shoulder and a shorter torso. If you typically wear a European 36 or UK 10, you may find that a Japanese M fits in the hip but pulls across the shoulders or sits too short in the body.
How we approach sizing at Tech Core Nex Wave ¶
We do not use Japanese S/M/L conventions. Our size range is XS to XL, and our measurements are in centimetres, calibrated against the actual bodies we fit in the atelier. When Haruka develops a new silhouette, she fits the toile on three different body proportions before finalising the pattern. The size guide on each product page gives bust, waist, and hip measurements for each size, along with a recommended size if you fall between two.
The torso length problem ¶
Torso length is the measurement most often ignored in swimwear sizing, and it is the one that causes the most fit problems. A swimsuit that is the right size in the bust and hip but too short in the torso will pull down at the front and ride up at the back. We include torso length in our size guide. Measured from the top of the shoulder to the crotch. Because it is the single most useful measurement for swimwear fit. If you are unsure of yours, we can measure you at the boutique.
When to book a fitting instead of guessing ¶
If you are between sizes, if you have a longer or shorter torso than average, or if you have had consistent fit problems with swimwear in the past, a fitting appointment is more useful than a size guide. We keep two same-day appointment slots free each day at the Daikanyama boutique. The appointment is complimentary and takes about an hour. You do not need to purchase anything on the day.
Sizing is not a fixed truth. It is a set of conventions that vary by brand, country, and decade. The only reliable method is to try the piece on, or to give us your measurements and let us advise. We would rather spend an hour getting the fit right than have you return something that did not work.