Vanity Sizing

Vanity sizing, also known as size inflation is used to refer to the phenomenon of ready-to-wear clothing of the same nominal size becoming larger over time. Vanity sizing tends to occur in places where clothing sizes are not standardized, such as the United States although within the United States it occurs far more frequently in women's apparel than in men's, partly due to the widespread and far earlier adoption of standardized measurement for men's apparel for military uniforms (where, for example, a pair of trousers with a 32" waist and a 32" inseam must be labeled as such regardless of who made it).

It is generally acknowledged that clothing of the same nominal size has become larger over the years. In 2003, a study that measured over 1,000 pairs of women's pants found that more expensive brands tended to be smaller than cheaper ones of the same nominal size. The increasing dimensions of garments of the same nominal size has caused some designers to introduce size 0, 00, or subzero sizes.

Many commentators have suggested that "vanity" sizing, as its name suggests, is designed to satisfy buyers' wishes to appear thin and feel better about themselves.

On the contrary, industry patternmaker Kathleen Fasanella argues vanity sizing is a myth, and that sizing entropy is the logical outcome of cutting to fit the increasing girth of the average customer. Product costing is tightly linked to the limitations of fabric cutting (so called "yield") upon which average per unit costs are based.

Different manufacturers have modified sizes so that a woman who once wore a size 12 dress can now wear a 10 or an 8. Depending on the brand, a size 8 dress can fit a woman with a bra band size ranging from 34 to 38 inches (86 to 97 cm), a waist measuring from 28 to 31 inches (71 to 79 cm), and hips measuring 36.5 to 41 inches (93 to 100 cm). Even a single brand can offer the same size in different measurements. Alix and Kelley, a manufacturer based in Los Angeles, offers different size 8 measurements, ranging from 35 to 38 inches (89 to 97 cm) in the bust. Size irregularities have existed for many years. In Sears’s 1937 catalog, a woman with a 32 inches (81 cm)-bust would have worn a size 14 dress. In 1967, the same woman would have worn an 8. In 2011, she would wear a zero.

However, other reasons for this change have been offered as well. Designer Nicole Miller's spokeswoman has suggested that 00 or subzero sizes were introduced in part because of the rise of Asian markets, where women are generally smaller. It has also been suggested that vanity sizing allows clothing companies to cater their sizing to their demographic, since women of different sizes may be attracted to different brands. Finally, it has been suggested that vanity sizing merely reflects the increasing prevalence of obesity.

Although vanity sizing is more common in women's apparel, men's clothing is not immune to it either. For example, men's pants are traditionally marked with two numbers, "waist" (waist circumference) and "inseam" (distance from the crotch to the hem of the pant). While the inseam label tends to remain accurate (for example, a pair of jeans labelled 34/32 would typically have a 32-inch inseam), the waist label may significantly understate the actual dimensions of clothing. In 2010, Abram Sauer of "The Esquire" measured several pairs of "waist 36" dress pants at different U.S. retailers and found waist circumferences ranging from 37 to 41 inches. The phenomenon has also been noticed in the United Kingdom, where a 2011 study found misleading labels on more than half of checked items of clothing. In that study, worst offenders understated waist circumferences by 1.5 to 2 inches. Market analysts say that the number of British men reporting varying waistlines from store to store has doubled between 2005 and 2011.