You wear a 9.5 in one sneaker and a 9 in another from a completely different brand, and both fit fine. Then a third brand's 9.5 slips at the heel and a fourth's pinches across the forefoot. None of this is you doing something wrong - it's the actual state of shoe sizing in 2026. Most size-conversion guides hand you a US-to-UK-to-EU table and move on, which is useful as far as it goes, but it doesn't explain why the number on the box still isn't reliable even after you've converted it correctly.
The workaround a lot of shoppers land on is ordering the same pair in two or three sizes and returning whichever ones don't work - a habit retailers call "bracketing." It solves the immediate problem, but it's an expensive way to solve it, and it's part of why footwear has some of the highest return rates in fashion e-commerce. Below is why the same labeled size shifts between brands and even between styles from the same brand, how specific brands tend to run, and a workflow that gets you to a confident single order instead of a bracket of three.
Footwear and apparel carry some of the highest online return rates in retail, commonly cited at 20-40% versus roughly 17% for all retail categories - and sizing or fit alone is estimated to drive 44-70% of those footwear returns, more than any other cause including damage or change of mind.
Why the Same Labeled Size Isn't the Same Shoe
A shoe size on the box is a label, not a measurement everyone agrees on. Unlike a tape-measure inseam, there's no government or industry body enforcing what a "9" has to mean, so every brand is free to build around its own reference foot. That single decision cascades into everything else that makes shoe shopping unpredictable.
01
Different lasts
The "last" is the foot-shaped mold a shoe is built around. Two brands' size 9 lasts can differ in length, width, and arch shape even when both claim the same US measurement.
02
Materials and construction
A stretchy knit upper, a rigid leather boot, and a canvas skate shoe behave completely differently on the same foot, even labeled the same size.
03
Category within one brand
A running shoe, a lifestyle sneaker, and a dress shoe from the same brand are often built on different lasts entirely - your size in one doesn't guarantee your size in another.
04
Regional systems stacked on top
US, UK, and EU scales already convert imperfectly - about half a size of wiggle room even in the best case - before a single brand's own quirks are added in.
How Specific Brands Tend to Run
This is shopper consensus built up over years of forum threads and return-rate patterns, not a lab measurement - and it can shift between a brand's own product lines. Treat it as a starting point for which half-size to try first, not a substitute for that specific listing's own chart.
| Brand |
General tendency |
Where it varies most |
| Nike | True to size, narrow through midfoot | Running vs. lifestyle lines |
| Vans | Runs small, especially canvas styles | Canvas vs. suede uppers |
| Converse | Runs small and narrow | Chuck Taylor vs. platform styles |
| New Balance | True to size, wider fit overall | Width options (available on some styles) |
| Adidas | Runs slightly large on many styles | Boost vs. classic sole lines |
| Dr. Martens | Runs large, needs a break-in period | Leather stiffness eases with wear |
The pattern that matters more than any single row: even a brand with a strong overall reputation for running "true to size" can still miss on a specific style, a specific material, or a specific run of stock. Why clothing sizes differ by brand covers the same dynamic for apparel, where vanity sizing adds yet another wrinkle.
The Real Cost of Guessing
Faced with sizing this unreliable, a common shopper response is bracketing: order the shoe in two or three adjacent sizes, keep whichever fits, and return the rest. It works, in the sense that you'll likely end up with a pair that fits - but it guarantees a 50-66% return rate on that single order by design, and it's part of why footwear return rates run so far above the retail average. Some retailers have started charging return fees or restricting accounts with frequent returns specifically in response to this pattern, which means the workaround is getting more expensive just as sizing inconsistency stays the same.
A narrower alternative to ordering three sizes
Spree
Compare candidates visually before you order any of them
Save the same style, or competing styles from different brands, into one wishlist as you shop - from a mainstream sneaker chain, a boutique boot maker, or a resale listing. Run AI Virtual Try-On on each candidate to preview silhouette and proportion on your own photo before you commit to a size, so the choice between brands happens before checkout instead of after three boxes arrive. It doesn't replace measuring your foot or checking that brand's own chart, but it cuts down on ordering multiple sizes of the same shoe just to compare them side by side.
Strengths
- Saves candidates from any store into one wishlist
- AI Try-On previews the real product on your own photo
- Compares brands side by side before you order
- Free, no ads, no data selling
Limitations
- Doesn't measure width or arch height - pair with the brand's own chart
- iOS only in 2026
- AI Try-On requires Pro plan
Any store
AI Try-On
Free + Pro $7.99/mo
A Workflow That Beats Ordering Three Sizes
A routine that replaces bracketing with a smaller number of more confident orders.
1
Measure your foot length and width once
Trace your foot on paper at the end of the day (feet swell slightly), measure heel to longest toe and across the widest point, and keep both numbers on hand for every future order.
2
Check that specific style's own chart - not your usual size
Your size in one brand's running shoe says nothing reliable about your size in a different brand's boot, or even a different line from the same brand.
3
Save every candidate into one wishlist
Get Spree from the App Store and add the pairs you're weighing across brands, so they sit in one place instead of scattered across browser tabs.
4
Preview each with AI try-on
Compare silhouette, proportion, and color on your own photo before you decide which one to actually order - narrowing the field before checkout, not after.
5
Order one size with a return window as backup
Confirm the store's return policy before you buy, so a genuine miss still has a fix - without needing to have ordered three sizes to get there.
For more on the numbers behind cross-region sizing, see the full US-UK-EU size conversion chart, and if a size still turns out wrong, how to reduce online clothing returns covers what to do next. Virtual shoe try-on goes deeper on the AI preview step specifically, and building a wishlist from multiple stores covers the saving workflow in more detail.
Frequently Asked Questions
Why do shoe sizes vary so much between brands?
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There's no single global shoe sizing standard enforced across manufacturers. Beyond that, every brand builds its shoes around its own "last" - the foot-shaped mold a shoe is constructed on - so a labeled size 9 can be shaped completely differently at two brands even if both claim the same US, UK, or EU measurement. Materials and category add another layer: a stretchy knit sneaker, a rigid leather boot, and a canvas skate shoe in the "same" size rarely fit the same way, even within one brand's own lineup.
Does ordering multiple sizes ("bracketing") actually work?
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It works in the narrow sense that you'll probably end up with a pair that fits, but it's an expensive and wasteful way to get there. Bracketing means ordering the same shoe in two or three sizes, planning to keep one and return the rest - which guarantees a 50-66% return rate on that order by design. Footwear already carries some of the highest return rates in fashion e-commerce, largely driven by fit and width, and a growing number of retailers now restrict or charge for frequent returns specifically because of this habit.
Which shoe brands run small or large?
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Shopper consensus (not a lab measurement) puts brands like Vans and Converse on the smaller, narrower side, especially in canvas styles, while Dr. Martens and many hiking boot brands are commonly sized up for a break-in period. Nike tends to run true to size but narrow through the midfoot, and New Balance is often recommended for wider feet. These are general tendencies, not guarantees - the same brand can run differently between a running shoe, a lifestyle sneaker, and a boot, so always check that specific style's own size chart rather than a size you remember from a different model.
How can I stop guessing shoe sizes when shopping online?
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Measure your foot length and width once and keep the numbers on hand, then check the specific listing's own size chart every time instead of relying on the size you wear elsewhere. Beyond that, save every candidate pair you're considering - across brands - into one wishlist and preview each with AI virtual try-on to compare silhouette and proportion before you order, so you're choosing one size with more confidence instead of ordering a bracket of sizes and hoping one works.
Is virtual shoe try-on useful for sizing?
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It's useful for a different half of the problem than a size chart solves. AI try-on shows you how a specific pair's silhouette, proportions, and color actually look on your own feet, which helps you choose between candidates and catch a style that just doesn't suit your foot shape. It doesn't measure width or arch height, so pair it with that brand's own size chart and your own foot measurements rather than treating it as a fit guarantee on its own.
The Bottom Line
Shoe sizing was never going to be simple once you accept that there's no enforced standard behind the number on the box - every brand, every material, and often every category within one brand's own lineup has its own idea of what a "9" means. Bracketing has been the default workaround for years, but it's an expensive habit that's getting more expensive as retailers push back on frequent returns.
The better version of the same idea is comparing candidates before you order, not after: measure your foot once, check each specific listing's own chart, and preview real candidates from different brands side by side so you're placing one confident order instead of three hopeful ones.