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Sizing Chart - Shirt

Size Guide

As a rough guide, take your usual size from other brands and follow the size guide table. For more detailed garment measurements, scroll further down.

Your Size S M L XL XXL
UK/US 36-38 38-40 40-42 42-44 44-46


Garment Measurements

Please find the approximate measurement of the garment in inches below to compare to items in your wardrobe.

Size (Inches) XS S M L XL XXL
Chest 18.9 19.9 20.9 21.8 22.8 23.8
Body Length 27.3 27.7 28.1 28.5 28.9 29.3
Sleeve Length 7.9 8.1 8.3 8.5 8.7 8.9


Chest 48.0 50.5 53.0 55.5 58.0 60.5
Body Length 69.5 70.5 71.5 72.5 73.5 74.5
Sleeve Length 20.0 20.5 21.0 21.5 22.0 22.5


How to measure:






Chest: Lay flat and measure across chest from armpit to armpit then double the measurement.

Body length: Lay flat and measure from the centre of the neck to the hem.

Sleeve length: Measure from the top of shoulder seam to the end of the sleeve.


If you are unsure what size is perfect for you and wish to speak to a team member, please email us at!

The Mission

undefined was created for the beginner, hobbyist, and competitor; regardless of sport or pursuit. In this day of age, so many of us are fixated on the end goal that we lose sight of the inherent beauty of the process and struggle. We as humans usually define ourselves by our achievements and losses.

Our mission is to inspire others to undertake challenges and constantly remind ourselves that the outcome isn’t what defines us. Willingness, persistence, and struggle are what Define us. Let your work, actions, and beliefs speak for yourself at the moment.

The Vision

Society often pressures individuals to conform their own identities to demographic or cultural standards. Here at UnDefined, we believe identities are not based on personal achievements or losses. It’s the character, grit, and willingness that individuals build and exhibit along the way, regardless of the pursuit. We’re here to remind you in spite of the outcome of the task at hand, it’s the perseverance to continue and see it through that matters.

Our vision is to become the world’s most authentic, inspirational, and community-driven functional fitness brand by developing high-quality, functional, and versatile products that are tried, tested, and proven with fitness communities around the world.

Use coupon code WELCOME10 for 10% off your first order.


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