Why Clothing Brands All Fit Differently – And How You Can Finally Get the Right Size Every Time

If you’ve ever been a size 10 in one brand and a size 14 in another, you’re not alone—and you’re not imagining it. Fashion sizing is inconsistent, confusing, and frustrating. That’s why understanding why brands size differently—and what you can do about it—can save you hours of dressing room trial and error or costly online returns.

This detailed guide breaks down the facts behind inconsistent clothing sizes, what affects sizing across brands, and how tellar.co.uk helps you find the right fit every time—without guessing, measuring tapes, or returns.

Why Do Brands Have Different Sizes?

1. There’s No Industry Standard for Sizing

Unlike shoe sizing (which tends to follow a relatively universal scale), clothing has no global or even national size standard. While size “Medium” might imply average, it can represent vastly different measurements across retailers.

For example:

• A UK size 12 at Zara often measures smaller than a UK 12 at Marks & Spencer

• US and European brands may use their own base measurements, leading to further confusion

Every brand creates its own size chart based on its target market, fit model, and style ethos. This is particularly problematic for online shoppers, who can’t try before they buy.

2. Vanity Sizing Has Skewed the System

Vanity sizing refers to the practice of labeling larger garments with smaller size tags to make shoppers feel better. While it might boost confidence in the short term, it wreaks havoc on consistency.

For instance:

• A UK size 10 today often equates to a size 14 from the 1990s

• High street fashion brands like H&M or Primark may run smaller to appeal to a younger demographic

• Premium and luxury brands sometimes run small to preserve a tailored, high-fashion silhouette

So a "size 12" at Topshop might not even fit your arm if you're a size 12 in White Stuff.

3. Fit Models Differ by Brand

Brands build their clothing patterns using “fit models”—real people used to represent a typical size. But the measurements of these models vary by brand.

• A brand targeting teenagers might use a petite frame with narrow shoulders and hips

• A brand targeting working women may favour broader shoulders and defined waists

This affects everything from sleeve length to waist placement, meaning you could wear a size 10 in one label and need a 14 in another—even if your body hasn’t changed.

UK vs EU vs US Sizes: The Conversion Nightmare

Even when brands provide international conversions, they’re rarely accurate:

• A UK 12 is often labelled as a US 8 or EU 40

• But in reality, an EU 40 can range from a UK 10 to 14 depending on the brand

Luxury European brands like Massimo Dutti, Maje, or Sandro tend to size small, especially compared to UK high-street counterparts like Next, Boden, or Whistles.

High Street vs Designer Sizing

Even within one store, sizing can vary. A pair of size 12 jeans might fit tighter than a size 12 dress from the same brand. That’s because manufacturers often outsource to different factories with different grading processes.

Size Charts: Useful—but Only If You Measure Yourself

Almost every brand publishes a size chart. But these charts assume you already know your:

• Bust (fullest point)

• Waist (natural bend point)

• Hips (widest point across buttocks)

The problem? Most people don’t have a measuring tape or don’t know how to measure correctly.

And even if you do, you still have to check every brand’s chart individually—a time-consuming and frustrating process.

The Tellar.co.uk Solution: Accurate Sizing Without Guesswork

✔ One-Time Login. Permanent Results.

tellar.co.uk solves the sizing chaos once and for all. With a one-time, free login, you can create a size profile in seconds. Just enter your three basic measurements—chest, waist, hips—and Tellar does the rest.

You’ll instantly see:

• Your best size across 1,500+ brands

• Detailed size charts per brand

• Notes like “This brand runs small in tops but true to size in trousers”

✔ No Tape Measure? We’ve Got You Covered

Don’t have a measuring tape at home? No problem. Tellar.co.uk offers a free printable measuring tape designed to work at home using just paper and scissors.

Download it here:

➡️ tellar.co.uk

✔ UK-Focused. Brand-Specific.

Tellar’s database includes only verified UK, European, and US brand data—adjusted for real body measurements, not vague size labels. You’ll get tailored recommendations based on:

• Body shape

• Style category (casual, formal, fitted)

• Material stretch and garment fit

The Top Sizing Tools Compared

Only Tellar.co.uk offers a complete UK-centric tool that’s completely free, accurate, and doesn’t require any purchase history.

Common Sizing Frustrations – Solved by Tellar

❌ “I’m a Medium in one shop and XL in another.”

✅ Tellar identifies your actual fit and lets you view your recommended size side-by-side across multiple retailers.

❌ “I don’t know if I’m buying something that will be too tight.”

✅ Tellar highlights which brands run small, large, or true-to-size—before you buy.

❌ “I shop online but hate returning stuff.”

✅ Tellar reduces returns by helping you get it right first time—no more trial-and-error guessing.

How to Get Started – In Under 2 Minutes

1. Go totellar.co.uk

2. Click “Create Profile”

3. Enter your measurements (or use the free printable tape)

4. View your size across 1,500+ brands instantly

Final Thought: You Deserve Better Than Guesswork

The fashion industry’s sizing system wasn’t designed with the modern consumer in mind. With no standardisation and confusing vanity sizing practices, shoppers are left to navigate a frustrating maze.

Tellar.co.uk changes that. With real-time size matching, verified data from over 1,500 brands, and a UK-specific focus, it’s the simplest way to take control of your wardrobe—and feel confident in your fit.

Start now. It’s free. It’s accurate. And it’s just one login away.

➡️ tellar.co.uk

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