Short answer: adidas doesn't run small as a brand. Individual models do, and the reason is that they were designed for different sports decades apart on completely different lasts.
Asking "do adidas run small" is a bit like asking whether cars are fast. Depends which one. Here's the breakdown.
Samba
The narrowest and most structured of the classic terrace models. It came out of indoor sport, where a snug fit was the point, and it runs slightly long as well as slightly narrow.
We put a half down, a true size, and a half up on the same foot, back to back. Go down a half if your feet are standard width or narrow. Take your true size if your feet are wide. Do not size up — at a half up the heel slips and the toe box sits empty. The leather gives across the width as it breaks in; it never gives in length. A width that feels snug on day one sorts itself out. Extra length never does.
Full detail in the Samba sizing guide.
Handball Spezial
The widest-fitting and most accommodating of the classic terrace models, which is the opposite of what that low, close-to-the-ground silhouette suggests.
True to size for standard-width feet. Go up a half if your feet are wide or you wear a medium-to-thick sock. Either way, lace it all the way up.
Full detail in the Handball Spezial sizing guide.
SL 72
The SL 72 runs long. It's narrow, with a long tapered toe box that leaves dead space up front.
True to size works for average and wide feet. Go down a half if your feet are slim, or if all that toe box bothers you. Wide feet should never size up in this one — the shoe is already long, and adding length only makes the dead space worse. More in the SL 72 sizing guide.
Superstar
The rubber shell toe makes the Superstar look roomier than it is. It isn't. The last is narrow, and the vamp pulls in over the shell toe — that taper is where a wide foot feels it first.
We tested the Superstar II a half down, true to size, and a half up on the same foot. True to size for standard-width feet. Wide feet get a trade-off rather than a clean answer: stay true to size and deal with any heel slip using a heel grip or a thicker sock, or go down a half if a locked-in heel matters more to you than toe room. Don't go up a half — the extra length did not fix heel slip in the test. On a genuinely wide foot, no single size in this shoe is perfect, and it's better to know that before you order.
See the Superstar sizing guide and the Superstar II size guide.
Gazelle
The Gazelle is the most true-to-size shoe in the lineup. It was a training shoe rather than a competition shoe, so it was built with a bit more room from the start, and the all-suede upper gives as it breaks in.
Take your normal size. Go up a half if your feet are wide or high-volume. More in do Gazelles run true to size.
Running models
Modern adidas running shoes follow running conventions rather than heritage ones, so they generally fit true to size with a bit more toe room. Knit uppers stretch with wear, so a snug fit out of the box usually settles. See the Ultraboost 1.0 sizing guide.
What if you have wide feet?
adidas heritage models don't come in width options, so the move is to pick a wider model rather than a bigger size. Going up a full size to gain width leaves you with a shoe that's too long, and your foot slides forward and jams the toe box anyway.
Ranked widest to narrowest: Campus 00s, Handball Spezial, Gazelle, Superstar II, Samba, SL 72. Start at the top of that list.
Two of those need a scope note so they don't read as contradictions. The Samba is the narrowest terrace model here. The Superstar II is narrow through the vamp — a rigid shell toe rather than a slim last. Two different kinds of narrow, both real.
How does kids' sizing work?
Sizes marked K are little kid. Sizes marked Y are grade school, and they use the same numbering as US men's — a 6Y is about a men's 6 and roughly a women's 7.5.
Other brands
If you're cross-shopping, we've covered whether New Balance run small as well.
Still deciding on a silhouette? Samba vs Gazelle vs Spezial compares the three that get confused most. Shop Sambas, Gazelles, Handball Spezials, and Superstars.
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