Adidas Size Chart

Start from the model’s own chart, not your other sneakers

adidas sizing looks consistent on paper and surprises people in practice, because the brand mixes European third-sizes, stretchy Primeknit uppers, and stiff classic leathers across one catalog. Begin every adidas purchase with a fresh measurement rather than a remembered size from another brand. Stand on a hard floor in the socks you plan to wear, measure both feet heel-to-toe in centimetres, and use the longer foot. adidas’s own fitting advice is to measure at the end of the day, when feet are at their largest. If you land between sizes, go down one size for a snug fit or up one for a roomier one.

There is one adidas-specific caveat worth knowing before you convert anything: the CM column in adidas size charts describes the sizing system rather than a direct foot-length measurement, so your measured foot may sit slightly above or below the chart value for the size you choose. Use the column as the stable reference for comparing sizes, then let the model’s fit note and your own try-on make the final call.

Why adidas EU sizes come in thirds

adidas is one of the few major brands whose EU scale steps in thirds. Between whole sizes sit two third-steps: after EU 42 come 42 2/3 and 43 1/3 before the scale reaches 43, and the pattern repeats all the way up. On the men’s chart, a US 9 is UK 8.5 and EU 42 2/3 with a listed CM around 26.3–26.4; on the women’s chart, US 8 is UK 6.5 and EU 40. The UK relationship also differs by gender chart: men’s UK runs half a size below US, while women’s UK runs 1.5 sizes below.

The practical rule is to quote the exact third-size from the model’s chart rather than rounding. Rounding 42 2/3 up to a whole 43 adds a third of an EU step you may not want in a performance shoe, and rounding down has the opposite effect. If a retailer’s checkout shows only whole EU sizes, compare the CM value instead and choose the step closest to your measured foot length.

Primeknit stretches; leather mostly does not

The upper material is often the real sizing variable in an adidas shoe. Primeknit models such as the Ultraboost fit like a sock: adidas’s own sizing guide describes the Ultraboost range as true to size for most people, with a half size up suggested for wider feet. Wearer reports follow the same pattern. The knit gives, but the rigid midfoot cage on the Ultraboost does not, so a snug midfoot is rarely solved by break-in. Some regional product pages go further and recommend sizing up based on return data, so always read the fit note on the specific listing rather than the model family as a whole.

Classic leather styles behave the opposite way. adidas describes the Stan Smith as unisex and true to size, and its smooth leather has limited give. It molds to the foot rather than stretching, so do not size down expecting the shoe to grow. The Samba’s leather softens through the forefoot after a few wears, but the model is consistently described as narrow, and adidas’s guidance is to go up half a size for wider feet. Treat “it will stretch” as a risk to manage, not a plan to rely on.

The classic models, model by model

The classic adidas silhouettes share a logo and not much else when it comes to fit. The Stan Smith is the most predictable: adidas positions the line as unisex and true to size, so buy your normal size and expect it to mold rather than stretch. The Superstar splits opinion by foot shape. The shell toe looks roomy from the outside but the interior is snug, and the advice runs from half a size down for narrow feet to half a size up for wide or high-instep feet, so start at your usual size and adjust only if you know which camp you are in. The Samba is the narrowest of the group across nearly all sources; adidas recommends a half size up for wider feet, while some narrow-footed wearers find the length slightly long and take a half size down. The Gazelle sits closest to true to size for most people, though reports of a narrow toe box and of variance between colorways both exist. None of this replaces the product page, but the pattern is a useful starting point: Stan Smith true, Superstar shape-dependent, Samba narrow, Gazelle mostly true.

Width, instep, and the European last

adidas classics are built on European lasts that wearers generally describe as narrower and lower in volume than the equivalent US size elsewhere, which is why “half a size up” appears so often in adidas fit guidance: the extra length is being used as extra width. That trade works better across the forefoot than at the heel. If a half size up leaves the heel slipping, the model is not right for your foot shape and no amount of extra length will fix it. Most adidas models are sold in a single width, so check the product page before assuming a wide option exists for the model you want. For the Superstar and Samba especially, decide using the widest part of your foot and your instep height, not just toe length.

Women’s-specific releases sit on a narrower last than the men’s versions of the same model, so a unisex pair and its women’s equivalent are different fits rather than the same shoe with two labels. When a listing shows both men’s and women’s sizing for one model, read the fit note for the version you are actually ordering.

Final checks before an adidas order

1. Measure both feet in centimetres at the end of the day, wearing your intended socks.
2. Open the size chart for the exact model and quote its EU third-size precisely.
3. Identify the upper material, Primeknit, smooth leather, or suede, and apply its stretch behaviour.
4. Check the model’s known fit tendency rather than assuming it matches your other adidas shoes.
5. Confirm width availability and heel hold before committing to a half size up for volume.
6. Try the pair indoors and verify the return window before any outdoor wear.

This is an independent educational guide and is not affiliated with adidas. Product measurements and fit notes can change, so confirm the current adidas listing and the retailer’s return policy before ordering.