Is ASOS True to Size? Its Own Size Charts Give the Size 10 Two Different Bodies (Topshop Just Moved Back In)
The Cara Delevingne Topshop capsule hit Asos.com yesterday, sized UK 6 to 18, so this question is about to get asked a lot. I didn't ask Reddit. I read the size charts ASOS prints on its own help pages, UK and US editions, on August 26. Then I read them again, because they don't match.
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The Topshop x Cara Delevingne capsule landed on Asos.com yesterday, 16 pieces, ÂŁ26 to ÂŁ95, sized UK 6 to 18. So a lot of shoppers, plenty of them American, are about to meet the question every ASOS basket eventually asks: which size am I here? The argument usually happens on Reddit and Mumsnet, where one thread swears ASOS runs big and the next swears it shrunk. I skipped the threads and pulled the charts ASOS prints on its own help pages instead, UK and US editions, on August 26.
We haven’t ordered anything. This is a desk read of the retailer’s published numbers, nothing more, and the numbers didn’t disappoint.
Is the ASOS size guide accurate?
ASOS publishes at least two size charts that disagree with each other: the dresses and tops guides put a UK 10 at an 88 cm bust and a 70 cm waist, while the sitewide chart on the US edition prints the same UK 10 at a 91 cm bust and a 72 cm waist. Three centimetres, over half a size step, between two pages of the same store. The bust ladders, side by side, both read the same day:
| Bust, per ASOS | UK 8 | UK 10 | UK 12 |
|---|---|---|---|
| Dresses & tops guides | 83 cm / 33 in | 88 cm / 35 in | 93 cm / 37 in |
| Sitewide chart, US edition | 81 cm / 32 in | 91 cm / 34 in | 91 cm / 36 in |
Look at that second row for a minute. The 10 and the 12 share one bust, 91 cm, while the inch cells claim they’re two inches apart. The 10’s own cells contradict each other too, because 34 inches is 86.4 cm, not 91. And the dual-size table below it gives the M bust as “91-78 cm,” a range that runs downhill. The conversion tables join in: the category pages call a UK 4 a US 0, the sitewide page calls it a US 1, a size US womenswear doesn’t print.
Does ASOS run small?
No single ASOS exists to run small: the charts describe ASOS own-brand clothing only, and the same page warns that “some brands may vary from these measurements but you can still use them as a guide.” Every partner label in your basket sits behind that caveat.
The in-house ranges drift too. ASOS Petite prints its size 12 at a 91 cm bust against the standard 12’s 93 cm, and Petite’s supposed to be shorter, not narrower. A forum verdict like “runs big” has to average across all of it, which is why the threads never settle.
And Topshop? The brand lives on Asos.com again, but it’s been 75% owned by Heartland since 2024, and when I opened the “Finding the right size” page on the relaunched Topshop.com, my reader got two headings and no numbers. Its cookie banner still says “browsing or shopping on ASOS.” The capsule’s UK 6 to 18 converts through whichever of those tables you happen to land on. Good luck.
The boring, workable answer: measure yourself, in centimetres, and shop the cm column of whichever chart the product links to. When I lined up seven brands’ charts on Monday, the imperial columns were where the mistakes lived, and ASOS’s 34-inch, 91 cm size 10 is the same disease.
Ignore the letter sizes entirely. You can skip the Reddit threads, and honestly you can skip the size number too: the chart won’t agree with itself, but a tape measure always does.