Why Your Shoe Size Changes Between Brands
The size you wear in one pair of shoes is useful information. It is not a guarantee that the same number will work in the next pair. Brands interpret sizing differently, and even two models from the same maker can fit differently.
Before ordering, look beyond the number and understand the shape you are putting your foot into.
Start with the last
A last is the form around which a shoe is made. It gives the shoe its toe shape, width, instep, heel and overall volume. A longer, slender last and a shorter, fuller one can carry the same size marking while feeling very different on your foot.
This is why knowing the last matters. Someone with a broad forefoot and narrow heel may struggle in a shape that suits someone with a fuller foot throughout. Going up a size can add room in one area while making the rest of the shoe too loose.
For a closer look at the forms used in shoemaking, see What Is a Shoe Last?, including my video explanation.
Check the sizing system, then the model
UK, US and European conversions are a starting point. Follow the sizing system and advice stated on the product you are buying rather than applying one conversion to every brand.
Width letters also need context. A letter that means standard width for one maker may mean something different for another. Read the description of the fit, not just its label.
Look for a secure fit, not a squeezed foot
New leather shoes should feel comfortably snug, with support around the foot. Snug does not mean painful or pinching. Leather will soften and settle with wear, but that is no reason to accept a shape that clearly does not suit you.
- Try dress shoes with the dress socks you intend to wear.
- Fasten the laces or straps properly before judging the fit.
- Pay attention to excessive heel movement and pressure across the instep.
- Do not judge an elongated shoe solely by empty space beyond your toes.
A gap between an Oxford’s facings does not, by itself, prove that you need a larger size. Consider how the whole shoe feels. My Shoe Fit guide explains these checks in more detail.
Give us useful comparisons
Read the product’s sizing guidance first. If you are unsure, contact us before ordering with the brand, model, last if known, and size of shoes that fit you well. Mention recurring issues such as a tight instep, loose heel or cramped forefoot.
That tells us much more than “I always wear a size 10.” For the fuller explanation, read Why Shoe Size Guides Are Not Universal.