What Is Sizing Like at Shein?

By Ella Blake — Fashion Stylist | Tellar Fashion Hub — Always honest, unbiased & unsponsored

Shein sizes small — often one to two full UK sizes smaller than you'd expect — and if there's one piece of advice I can give you before you click "add to cart," it's this: always, always size up and check the individual product measurements, because their sizing is anything but consistent across ranges.

I'll be honest — I've had a few Shein disasters in my time. A slinky midi dress that arrived looking more like a belt. A set of wide-leg trousers that I had to wrestle over my hips despite being my "usual" size. But I've also had some genuine wins: a gorgeous faux-leather blazer that looked ten times its price, ordered two sizes up based on the cm measurements, and it fit like a dream. The key? Treating Shein sizing like its own separate language — one you have to learn.

The Shein Sizing System Explained

Shein doesn't operate on a standard UK or EU sizing framework. Instead, they use their own size labels — XS through to 6XL — with measurements given in centimetres. The important thing to note is that these measurements can vary quite dramatically between product lines and even between individual garments within the same "size." A dress listed as a Medium in one range might have completely different dimensions to a Medium in another.

Here's a general guide to Shein's sizing versus UK equivalents — but please do treat this as a starting point only, and always cross-reference with the specific product's cm measurements:

Shein to UK Size Conversion (Women's)

Shein SizeUK Size (approx.)Bust (cm)Waist (cm)Hips (cm)XS6 – 880 – 8462 – 6687 – 91S8 – 1084 – 8866 – 7091 – 95M10 – 1288 – 9270 – 7495 – 99L12 – 1492 – 9674 – 7899 – 103XL14 – 1696 – 10078 – 82103 – 107XXL16 – 18100 – 10482 – 86107 – 111XXXL18 – 20104 – 10886 – 90111 – 115

How Shein Sizing Varies by Garment Type

This is where it gets really important, because different garment categories behave very differently on Shein. Here's what I've found — both from personal experience and from trawling through thousands of customer reviews:

Tops & T-shirts: Generally size up by one. Shein tops often run narrow in the shoulders and short in the body. If you're long-waisted, go up two.
Dresses: Size up one to two sizes. Bodycon styles in particular are cut extremely slim. For midi and maxi dresses, measure your hips carefully — the waist-to-hip ratio on Shein dresses is often quite narrow.
Jeans & Trousers: Size up at least one, sometimes two. Shein jeans can be painfully tight in the thighs and hips even when the waist fits. Look for styles with stretch fabric if you can.
Jackets & Outerwear: Size up two sizes minimum. These tend to be the most drastically undersized pieces on the whole site. A Shein blazer that's meant to sit open can end up looking like a straitjacket if you don't account for shoulder width.
Knitwear & Loungewear: These are often the most forgiving — you may only need to go up one size, and some styles are actually true to size. Still check the cm measurements, especially sleeve length.
Swimwear: Size up at least one to two. Shein swimwear cups tend to run small and the body panels tight. Read the reviews religiously on these.

My Golden Rules for Shopping Shein

Ignore the size label entirely — work only from the garment's cm measurements
Measure yourself properly: bust, waist, and hips, and compare directly to the product page chart
Read customer reviews and look for photos from real buyers — Shein's review section is actually one of its most useful features
When in doubt between two sizes, always go up
Be prepared for inconsistency — what fits perfectly from one Shein range may not be the same experience in another

High Street Brands with More Reliable Sizing

If Shein's sizing lottery feels a little exhausting — and believe me, I understand — there are plenty of high street options offering similar trend-led styles with far more predictable sizing. Here are my picks, chosen based on genuine style-magazine coverage and customer reviews, not just because they're the obvious first names that come to mind:

Mango — Consistently brilliant for trend-driven pieces. Their sizing runs slightly slim but is predictable once you know your Mango size, and the quality-to-price ratio is genuinely impressive.
H&M — A reliable go-to for on-trend basics at Shein-comparable prices, with far better sizing consistency. Their extended size range is also much more inclusive.
River Island — Brilliant for going-out looks, bold prints, and denim. Their sizing has improved significantly and tends to run true to UK size.
ASOS — The sheer range rivals Shein, but ASOS's returns process and fit notes per garment make it a considerably safer bet for online shopping.
New Look — Criminally underrated. Incredible value, genuinely on-trend, and the sizing is much more consistent than Shein. Their petite and tall ranges are also worth exploring.
Topshop — Now available via ASOS, the Topshop edit still delivers solid trend pieces with familiar UK sizing. A great middle ground between fast fashion and a more curated feel.
Urban Outfitters — For that slightly more editorial, eclectic aesthetic that Shein often tries to replicate, Urban Outfitters does it with better fit and more interesting fabrication.
Boden — If you're after something with longevity and a more classic-meets-colourful sensibility, Boden's sizing is spot-on and their quality is a genuine step up.

Premium & Independent Picks Worth Knowing About

If you're thinking about redirecting even a fraction of your Shein budget into fewer but better pieces, these are worth considering:

Reiss — For elevated workwear and occasion pieces, Reiss sizing is consistent and sophisticated. A well-cut Reiss dress will last years.
Me&Em — One of the best premium high street brands in the UK for wearable, grown-up style. Their sizing is generous and accurate, and the pieces genuinely earn their price tag.
Nobody's Child — An independent sustainable brand that's become a genuine favourite of style editors. Great size range, ethical credentials, and the prints are genuinely lovely. Their sizing runs true to UK.
Kitri — A small, independent London label with a cult following. Their dresses and skirts are made in limited runs, fit beautifully, and are about as far from disposable fashion as you can get while still feeling fun and wearable.

📖 More from the Tellar Fashion Hub:

Stop Guessing Your Size. Use Tellar.

Shein's sizing inconsistency is exactly why Tellar exists. We've built the UK's leading sizing tool — matching your measurements to over 1,500 brands instantly, so you never have to second-guess a size chart again.

✦ Measure once — bust, waist, hips, or use a brand size you already know
✦ Use the Store Size Lookup to find your exact size in any brand
✦ Covers 1,500+ brands — from Shein to Chloé and everything in between
✦ Always free. No downloads. Works in your browser.

Visit Tellar Store Size Lookup Tool

Tellar Fashion Hub — honest, unbiased, and always free. We are not sponsored by any brand featured in this post.