Understanding Why Brand Sizing Varies — And How to Take the Guesswork Out with Tellar.co.uk

Navigating clothing sizes is one of the most frustrating aspects of modern fashion. A size 12 in one brand may feel like a size 10 in another—or a 14 somewhere else. This inconsistency isn’t just inconvenient; it leads to wasted time, costly returns, and customer dissatisfaction.

This guide explores the reasons why sizing differs across fashion brands and how Tellar.co.uk eliminates the confusion with a precise, data-driven approach to finding your perfect fit.

Why Clothing Sizes Differ So Widely

1. No Industry Standard

There is no universally accepted sizing system in the fashion industry. Each brand develops its own size chart based on:

Internal design specifications
Target customer profiles
Proprietary fit models

As a result, a UK size 12 in Zara may match the dimensions of a size 10 in Whistles or a size 14 in White Stuff.

2. Vanity Sizing and Brand Strategy

Vanity sizing—labelling larger clothes with smaller sizes—has further distorted the landscape:

A UK 12 at Marks & Spencer may be equivalent to a UK 14 at H&M
Premium labels often run small to maintain a designer aesthetic
High street brands sometimes run large to cater to mass-market preferences

These strategic sizing decisions serve branding goals but make shopping incredibly inconsistent for consumers.

3. Global Size Discrepancies

International conversions add another layer of complexity:

A UK 12 typically translates to a US 8 or EU 40, but these vary widely by brand
European brands like Massimo Dutti, Maje, and Sandro often size smaller than UK brands
American brands such as Abercrombie and J.Crew usually run larger than their UK equivalents

Even when conversion charts are available, they’re rarely reliable without context.

The Problem with Size Charts

Brand-specific size charts are helpful only if you:

Know your exact measurements
Understand where and how to measure
Trust that the chart reflects current product specs

Unfortunately, many shoppers:

Don’t own a measuring tape
Aren’t sure how to measure properly
Are unaware that sizing can differ within the same brand (e.g. tops vs trousers)

Even a “size 10” top and a “size 10” dress from the same brand may fit completely differently based on the cut, fabric, or collection.

Fabric and Design Impact Fit Too

Beyond brand and region, garment material and construction play a crucial role in sizing:

Fabric or Style Factor	Impact on Fit
Stretch materials (e.g. Lycra, elastane)	Offers more flexibility and fit forgiveness
Tailored or structured styles	Fit closer to the body, may feel tighter
Oversized or relaxed cuts	Often appear larger than labelled size

A "Medium" in a structured Reiss jacket may fit smaller than a "Medium" viscose top from COS, simply due to cut and fabrication.

Sizing Philosophy: High Street vs Designer

Category	Typical Fit Profile
High Street Brands	Generally true to size or slightly large
Fast Fashion	Often inconsistent or runs small
Luxury & Designer	Tailored and tends to run small
Plus Size Labels	Varies significantly across retailers

Understanding a brand’s sizing intent helps, but isn’t always practical—especially when shopping across multiple retailers online.

The Smart Solution: Tellar.co.uk

Tellar.co.uk removes the uncertainty by offering precise, measurement-based sizing guidance across 1,500+ UK and international brands. It’s a completely free, one-time login tool that delivers instant results.

✔ Build Your Personal Sizing Profile

Input three simple measurements—bust, waist, and hips—and Tellar calculates your best-fitting size across every supported brand. It’s quick, private, and doesn’t require multiple signups.

👉 Create your free profile

✔ No Tape Measure? No Problem

Tellar provides a free, printable measuring tape that you can download directly from the website.

👉 Download your free measuring tape

This enables accurate self-measurement at home without needing any special tools.

✔ Tailored Sizing for the UK Market

Tellar focuses on the UK market, factoring in brand-specific fit trends, fabric behaviour, and style categories (tops, trousers, dresses). It’s continuously updated to reflect the most accurate fit recommendations.

How Tellar.co.uk Stands Out

Feature	Tellar.co.uk	ASOS Fit Assistant	TrueFit (Fit Finder)
UK-Focused Fit Recommendations	✅	✅	❌
Free to Use	✅	✅	❌
Based on Actual Measurements	✅	❌ (purchase data)	✅
No Purchase History Required	✅	❌	❌
Brand Coverage	1,500+ brands	Limited	Partner-only brands

Only Tellar.co.uk offers real-time, UK-specific sizing at this level of detail—for free.

Common Sizing Struggles—Solved by Tellar

“I’m a size 10 in one store and a size 14 in another.”

✅ Tellar compares your personal measurements against each brand’s unique size chart.

“I’m tired of returning clothes that don’t fit.”

✅ Accurate sizing upfront reduces costly online returns.

“I never know what size to buy when I try a new brand.”

✅ With Tellar, you’ll see the correct size recommendation immediately—even for unfamiliar labels.

How to Use Tellar in 3 Simple Steps

Visit www.tellar.co.uk
Create your profile with bust, waist, and hip measurements
Search your brand and receive instant, personalised size recommendations

Final Thought: Say Goodbye to Guesswork

Fashion sizing has never been truly standardised. From fit models and brand positioning to international conversions and fabric choices, the system is designed to serve brands—not shoppers.

Tellar.co.uk is changing that.

With real measurement-based sizing, personalised recommendations, and UK-focused brand insights, Tellar puts control back in your hands—so you never have to guess your size again.

Find your true fit today – it’s free and easy.

👉 Start at Tellar.co.uk

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