When you pull a new Under Armour garment from the shelf, the first question is often whether it will fit comfortably or require a size adjustment. Understanding whether Under Armour runs big or small is essential for securing the perfect fit, and the answer is not a single rule but a spectrum that depends heavily on the specific product line and construction. While some classic T-shirts and tops fit true to size, many of their performance tops, hoodies, and outerwear pieces are intentionally designed with a slightly generous cut that can feel roomier than standard athletic brands. This guide breaks down the brand’s sizing tendencies across different categories to help you make a confident decision the first time.
General Sizing Philosophy Across the Brand
Under Armour’s overarching sizing strategy is built for movement rather than strict conformity to standard vanity sizing. Unlike fashion brands that size small to create a slimming illusion, Under Armour prioritizes a functional fit that allows a full range of motion. For many everyday items like cotton T-shirts and casual polos, the brand generally aligns with a true-to-size fit that you would expect from a standard men’s or women’s cut. However, once you move into their technical gear—such as performance jackets, training pants, and layered apparel—the fit often shifts to a slightly oversized template that provides extra room for layering and athletic activity.
Category-Specific Fit Tendencies
To navigate whether a specific item will run big or small, it helps to break down the collection by garment type. The brand’s approach to fit is deliberate: a running T-shirt is meant to be lightweight and non-restrictive, while a insulated jacket needs enough space to accommodate a heavy base layer. By looking at the purpose of the garment, you can predict how the size will compare to your standard measurements.
Tops and T-Shirts
In the core tops category, including standard T-shirts, polos, and casual sweatshirts, Under Armour typically runs close to a true size. If you usually wear a Medium in a standard brand, you will likely find a comfortable fit in the same size here. The fabric is designed to drape naturally without clinging, making it a reliable choice if you prefer a straightforward, no-fuss fit without having to size down.
Performance and Training Gear
When you look at technical training tops, compression shirts, and performance jackets, the brand often leans toward a slightly larger fit. This is by design; these pieces are engineered to fit over base layers or to provide a relaxed range of motion during high-intensity workouts. If you are between sizes or comparing these items to a slim-fit brand, you might find that sizing up provides the optimal balance of comfort and functionality without drowning your frame.
The Influence of Fabric and Construction
The feel of the fabric and the method of construction play a significant role in how the clothing drapes on your body. Under Armour utilizes a variety of synthetic blends designed for wicking and breathability, and these materials often behave differently than standard cotton. Some textures lie smooth against the skin, creating a streamlined look, while others have a subtle structure that adds volume. Additionally, the stitching and seam placement can create visual bulk, which might make a garment appear smaller than the actual cut, so it is important to rely on measurements rather than how the tag suggests it should fit.
How to Choose the Right Size
Navigating the fit successfully comes down to understanding your body measurements and comparing them to the brand’s specific size chart rather than assuming your usual numerical size is universal. Because Under Armour operates across multiple categories—from casual wear to technical gear—the fit can vary based on the intended use of the garment. Taking the time to measure your chest, waist, and inseam ensures you can decode whether a specific item is meant to be a true fit or if it deviates from the norm.
