Why you can have two different sizes

Sep 20, 2026

Short answer: Upper and lower body do not follow the same scale, which is why many people wear one size on top and another below. That is normal and not a problem. It just means choosing your size by the measurement that matters for each type of garment.

A size is an average

A size guide is built on an average of many bodies. It assumes that bust, waist and hips grow evenly from one size to the next. Very few bodies follow that scale exactly. So it is completely common to fit one size on top and another below, and it says nothing about whether your body is right.

Bodies are not proportional

A large bust does not automatically come with large hips, yet the size guide assumes it does. Some people have broad shoulders and narrow hips, others the opposite. That is why bamboo t-shirts for women and trousers rarely fit in the same letter, and choosing them separately is perfectly fine.

The right measurement for each garment

Each type of garment has its own deciding measurement. Tops are chosen by bust, trousers and skirts by hip and waist. Socks are chosen by foot length. Once you know which measurement applies to which item, choosing correctly becomes simple, even if your sizes are not the same across your body.

Buy the pieces separately

Choose the size by the measurement that matters for that type of garment. This also applies to bamboo slips, which follow the bust measurement because they hang from the shoulders. When you buy each piece on its own, you get a fit that works both on top and below, instead of compromising on one of them.

Sets force a compromise

When you buy a set, you have to choose by the piece that fits closest. If that is the top, the trousers may be too large, and the other way round. Buy the pieces separately when you can. See socks for women as an example of an item with its own size, separate from the rest.

Stretch can bridge the gap

Soft knits with stretch can cover a small difference between two sizes. A fabric with elastane gives and adapts to the body, so a single size often fits both top and bottom. If the difference in your measurements is large, though, it is still best to choose each piece by its own measurement.

Keep track of your sizes

Write down which size you wear in tops, bottoms and socks, ideally with your measurements. Then you do not have to guess next time you shop. The list is also useful if you want to wish for something, or if someone else wants to buy you a gift and get it right first time.

It is not a problem

Having two sizes is completely normal and applies to most people. It is not a sign that anything is wrong with your body or with the clothes. It is simply how size guides work. Once you know that, choosing becomes easier, and you get clothes that fit well from the first day.