Shoppers often assume the clothing sizes XL and 1X represent the same physical dimensions labeled differently. These two sizes, however, originate from separate industry sizing systems designed to fit fundamentally different body shapes. Understanding the distinction between the standard and the plus-size systems is the first step in finding the perfect fit.
Standard vs. Plus Sizing Systems
The size XL belongs to the “Misses” or standard sizing system, which uses sequential letters to denote increasing size, such as S, M, L, and XL. This system is traditionally graded for a body that maintains a relatively consistent increase in circumference across the bust, waist, and hip as the size increases. The pattern grading rule for standard sizes typically increases the circumference by a uniform amount for each step up in size.
The size 1X is the starting point for the distinct “Plus” sizing system, represented by a number followed by an ‘X’. This system was developed to accommodate a different body distribution, where volume is often carried more centrally in the torso and upper back. The shift from a letter-based system to a number-X system signals a change in the foundational approach to garment design and fit.
This distinct classification means the jump from XL to 1X is not merely the next step in a linear progression of size. Instead, it marks the transition to a pattern cut intended for a different underlying body morphology, altering the garment’s entire framework.
How XL and 1X Differ in Measurements and Cut
Although the bust or chest circumference measurements of XL and 1X may occasionally overlap, the differences in proportion and cut are significant. The pattern for 1X is constructed with a greater allowance for the waist and hip circumference relative to the bust measurement. This results in a garment that offers more material around the torso and midsection compared to XL, which is designed for a more streamlined fit.
The proportional differences extend to the upper body and sleeve construction. A 1X garment typically features a deeper and wider armhole, sometimes referred to as the armscye, to provide comfort and prevent constriction across the back and shoulders. This deeper cut accounts for the greater volume often found in the upper arms and across the upper back of the body shape the Plus system is designed to fit.
The length of the garment is often adjusted between the two sizing systems. Plus-sized clothing, including 1X, is generally designed with a longer torso length and a greater back width to accommodate a fuller frame. The grading rules, the technical instructions used to scale a pattern, change substantially when moving from Misses to Plus, prioritizing width and depth over a simple increase in overall diameter. These dimensional adjustments mean the two sizes feel and drape differently on the body.
Practical Guide: Choosing the Right Fit
Shoppers should use their specific body shape and weight distribution as the determining factor when choosing between XL and 1X. If the main concern is height, length, or width across the shoulders and bust while maintaining a relatively slender waist, XL is the more appropriate option. This size provides the necessary shoulder room without adding excessive fabric volume to the midsection.
If a person requires more circumference in the stomach, waist, or hip area, the 1X garment provides a more comfortable and flattering fit due to its fuller cut and adjusted proportions. The additional depth in the armholes and extra fabric across the back in the 1X size are specifically designed to eliminate pulling and binding. Focusing on the fit in the torso, rather than just the bust, is a reliable method for making this choice.
Because sizing is not standardized across all brands, consulting the specific size chart provided by the retailer is recommended. These charts often provide the actual garment measurements, allowing for a precise comparison against personal body measurements. Reading the product descriptions for terms like “relaxed fit” or “straight size” can provide additional clues about the intended shape of the clothing.