Certified Sports has carved out a bold identity in the UK streetwear and activewear scene. Known for heavyweight fabrics, strong branding, and limited-edition drops, the brand appeals to those who want their clothing to feel premium, structured, and substantial.

But when it comes to sizing, Certified Sports can be a challenge. Oversized silhouettes, unisex cuts, and frequent design updates mean it’s not always obvious what size to buy. If you’ve ever asked “What size am I in Certified Sports?” — you’re not alone. Here’s everything you need to know.

Why Certified Sports Sizing Is Difficult to Judge

Unlike traditional fashion brands, Certified Sports doesn’t follow strict sizing consistency across collections. While the brand uses standard UK size labels (Small, Medium, Large), the actual fit is often oversized and designed to sit looser on the body — sometimes by as much as a full size.

What affects sizing:

Drop-shoulder constructions
Boxy, relaxed fits
Thicker cottons and fleece that don’t stretch
Limited public data on their fit model measurements

If you're ordering without trying on, the safest bet is to compare your best-fitting oversized brand (like Trapstar, Represent or Corteiz) to Certified’s size chart — or better yet, use Tellar.co.uk to match your measurements instantly.

Find Your Certified Sports Size in Seconds

We’ve analysed over 1,500 fashion brands so you don’t have to.

At Tellar.co.uk, you can enter your measurements or a brand you already wear and get your best size match for Certified Sports — based on real sizing data, not just guesswork.

Try it here now — it’s completely free to use, takes under a minute, and helps avoid costly sizing mistakes.

Certified Sports Size Conversion Guide

Size	UK (Men)	Chest (cm)	Waist (cm)	Notes
XS	6–8	84–88	70–74	Slim fit for petite frames
S	8–10	89–93	75–79	Relaxed on small builds
M	10–12	94–99	80–85	Best-selling size
L	12–14	100–105	86–91	Intended to sit loose
XL	14–16	106–111	92–97	Drop-shoulder is exaggerated
XXL	16–18	112–118	98–104	Designed for oversized look

If you’re between sizes or not used to relaxed fits, consider sizing down unless you prefer the boxy Certified aesthetic.

How Certified Sports Clothing Fits (By Category)

T-Shirts

Made from thick 250–300gsm cotton
Boxy through the chest and arms
Slight drop in shoulder seam
Fit Tip: Most users find these fit a full size large. Size down for a regular fit.

Hoodies

Oversized by design
Ribbed hem can sit tightly at the waist while body remains loose
High-quality fleece can feel bulky
Fit Tip: Stick to your true size if you want the oversized streetwear look. Size down if you prefer something closer to the body.

Tracksuits / Joggers

Tapered fit from thigh to ankle
True to size through the waist, looser in the legs
Fit Tip: Go with your normal size unless you prefer a very snug taper, in which case size down.

Outerwear & Coats

Often cropped or padded
Minimal stretch, so check chest size
Fit Tip: Fit is accurate, but check shoulder and chest measurements before buying. Use Tellar.co.uk if you're unsure.

How Does Certified Sports Compare to Other Brands?

If you already wear brands like:

Represent
Trapstar
Corteiz
Hoodrich

…then Certified Sports will likely run a bit larger than these — especially in tops and hoodies. Many users report that a Medium in Corteiz feels like a Large in Certified.

Still unsure? Get a personalised match on Tellar.co.uk.

Avoid Wasting Time (and Returns)

Certified drops often sell out quickly. You don’t want to miss a limited restock just because the fit wasn’t right.

That’s where Tellar.co.uk comes in.

You can:

Get your exact Certified Sports size match
Store your profile for future drops
Compare sizing across over 1,500+ brands
Use your actual body measurements — or start with a brand you already wear

Stay One Step Ahead

Don’t wait until you’ve bought the wrong size.

Join thousands of users already using Tellar.co.uk to get accurate sizing advice for Certified Sports and every other brand in your wardrobe.

All it takes is one quick setup — and you’ll never need to second-guess sizing again.

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