What Is Sizing Like at AYBL?

AYBL runs true to size – but here's the catch nobody warns you about: the fit swings dramatically depending on which range you're buying. Order your usual size and you'll be right most of the time. The problems start when a man buys a snug Ascend seamless tee and a baggy Essential hoodie in the same size and wonders why one clings and one drowns him. Both are "true to size." They're just built to sit very differently on the body.

The short answer

AYBL themselves state that every style runs true to size, and after dressing a fair few gym-going clients in it, I'd agree – with a caveat. AYBL isn't one fit, it's several. The seamless ranges are cut close to flatter a trained physique. The oversized ranges are cut generously on purpose. So "what size am I in AYBL?" is the wrong question. The right one is "what am I buying, and how is it meant to sit?"

How AYBL actually fits, range by range

Ascend (seamless): This is the muscle-hugging stuff – a nylon-elastane blend that stretches and clings to every line of the torso. It's a regular seamless fit, so take your normal size. If you're carrying real size across the chest and shoulders and you want breathing room, don't size up; just accept it's designed to be fitted.
Essential & oversized tees, hoodies, joggers: Deliberately roomy. These are cut big by design, so resist the urge to size up. Your true size already gives you that dropped-shoulder, streetwear silhouette. Go a size up and you'll swim.
Core shorts (5" and 7"): True to size on the waist. The 5" reads sportier and shows more leg; the 7" is the safer, more universally flattering length.
Sport cargo trousers & zip joggers: Relaxed through the leg, true on the waist. Great over trainers, less so if you want a tapered, tailored line.

A quick word from experience

Early on I kitted a client out entirely in AYBL for a shoot – strong lad, big through the shoulders – and I let him talk me into sizing up the Ascend tee "for comfort." It looked like a bin bag on camera. We reshot in his true size and it was night and day: the seamless cut was doing exactly what it was designed to do, and my "safe" call had undone it. Lesson learned. With this brand, trust the size on the label and trust the cut.

Getting your size spot on

Take two measurements before you order: your chest at the fullest point, and your natural waist just above the hips. AYBL's own fit tip is worth knowing – if your waist sits one size below your hips, size up; if it's two sizes below, take the size in between. And if you're genuinely on the border, size down in the seamless ranges for that locked-in feel, and stay true in the oversized ones.

Where else to shop – my brand picks

AYBL is affordable, on-trend and a strong shout for seamless gym kit. But if you're building a proper wardrobe, spread your net. Here's where I'd send clients across three tiers.

High street: Gymshark for the closest like-for-like on fitted seamless training gear at a comparable price; Under Armour for genuinely technical, sweat-wicking performance layers; and Castore for a sharper, British take on premium-feeling basics.
Independent / boutique: Montirex for standout British design that reads as sportswear and streetwear at once; Represent 247 for elevated gym pieces with a fashion-led cut; and Darc Sport for heavyweight oversized fits with a real cult following.
Designer / luxury: Lululemon for the best fabric and construction money can buy in athleisure; On for Swiss-engineered performance that looks the part off-duty; and Y-3 (adidas x Yohji Yamamoto) when you want genuine designer athletic wear that transcends the gym entirely.

What's on trend right now leans firmly into the AYBL playbook: fitted seamless on top, roomier on the bottom, tonal colours over loud logos. Nail the proportion – snug where you've trained, relaxed everywhere else – and you'll look considered rather than kitted-out.

Stop guessing your size – know it

The reason so many men get AYBL wrong is simple: they're guessing. Tellar is the UK's leading sizing tool, and it takes the guesswork out entirely. Measure once – chest, waist, hip, or just your size in a brand you already own – and Tellar matches your body precisely to over 1,500 brands, instantly. No more squinting at size charts.

Measure once and you're set for life – use your measurements or an existing brand size.
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