meet your typical

Like many girls her age, she loves to keep up with the latest fashion trends and explore new ways to express herself. Shopping is fun, but it won’t always be this way.

Scroll

XXSXSSMLXLXXL

“Junior’s” clothing lines often channel tweens’ interests with youthful styles that fit young girls as they grow.

For now, our typical (or median) 11-year-old wears a size 9 in the junior’s section, which is also considered a size Medium.

But not all tweens wear the same size.

If we were to look at a sample of all 10- and 11-year-old girls in the U.S. from the National Center for Health Statistics, here are the junior’s sizes that match up with their waistline measurements.

By age 15, most girls have gone through growth spurts and puberty, and they’ve reached their adult height.

Many have started to outgrow the junior’s size section.

This marks an important turning point as they shift into women’s sizes.

Girls who fall along the bottom 10th percentile can now wear an Extra Small in women’s clothing, while girls near the 90th percentile will find that an Extra Large generally fits.

The median 15-year-old wears a Medium, as she has throughout most of her childhood.

This means for the first time ever, most girls in their cohort will be able to find a size in the women’s clothing section.

This will also likely be the last time this ever happens in their lives.

fit 4 a

By Amanda Sakuma

with Jan Diehm

I remember once being that teen girl shopping in the women’s section for the first time. I took stacks upon stacks of jeans with me to the dressing room, searching in vain for that one pair that fit perfectly. Over 20 years later, my hunt for the ideal pair of jeans continues. But now as an adult, I’m stuck with the countless ways that women’s apparel is not made for the average person, like me.

Children’s clothing sizes are often tied to a kid’s age or stage of development. The idea is that as a young person grows older, her clothes will evolve with her. Youth styles tend to be boxy and oversized to allow room for kids to move and grow. By early adolescence, apparel for girls becomes more fitted. Junior’s styles have higher waistlines and less-pronounced curves compared to adult clothing lines. In short: clothes for tweens are made for tween bodies.

By the time most teenage girls can wear women’s clothes — around age 15 — their options are seemingly endless. But the evolution in clothing sizes that followed girls throughout childhood abruptly stops there.

This is the reality I find myself reckoning with today: Women’s clothing — designed for adults — fits modern teen girls better.

Age: 14-15

Sizes: Women's

Waistline in Inches

XXSXSSMLXLXXL

At age 15 a size Medium still equals the median waistline but, from here on, the two will diverge.

In addition to generic letter sizes (Small, Medium, Large etc.), women have a numeric sizing system that is designed to be more tailored and precise. Here, the median 15-year-old’s waistline fits a size 10.

The median 20-something will eventually move up a letter size to a Large.

In U.S. women’s sizing, this translates to a size 14.

Her wardrobe will shift again in her 30s.

At this point the median woman is closer to a size 16 or Extra Large.

This trend will continue again, and again.

Altogether, the median adult woman over the age of 20 fits a size 18.

The problem is that most “Straight” or “Regular” size ranges only go up to a size 16.

That leaves millions of people — over half of all adult women — who are excluded from standard size ranges.

Pain is sizing is not

Few life experiences feel as universal, across generations, as the pains and frustrations of trying to find clothes that fit.

Sizes vary wildly from store to store. Even within a single apparel company, no one size is consistent. There are no regulations or universal sizing standards. Instead each brand is incentivized to make up its own. When size guides change — and they’re always changing — brands are not obligated to disclose updates.

There are also often different sizing structures for every type of garment. “Plus” size means one thing, “curve” means another, and “extended” sizes can be defined as all of the above or something else entirely. Don’t count on any of those sizes to be available to try on in-store, but do brace for return fees if your online order doesn’t fit. Free in-store alterations are largely a thing of the past, while a trip to the tailor’s can cost just as much as the item itself.

The only consistent feature is that the industry at large continues to cling onto the same underlying sizing system that’s been broken for decades. And it’s only gotten worse.

Waistline in Inches

ASTM

Age 15

median

30.4"

Adult

median

37.7"

Size range:

Letter size:

Numeric size:

Waist size: "

While there are no universal sizing standards, an organization called ASTM International regularly releases informal guidelines.

Here, each current ASTM size (00–20) is represented by a dot.

Clothing manufacturers may loosely follow those standards, but more often than not, brands prefer to tailor their own practices to their target customer base.

These dots represent the size charts of 15 popular brands. Dots connected by a shaded background show when measurements or sizes are presented as a range.

Sizes are frequently inconsistent and undefined.

Generic letter sizes often group multiple numeric sizes together, with no universal standard for what “Small” or “Medium” actually means. For example, here’s every size that is labeled as Large, spanning waistlines from 29 to 34 inches.

Here is our median 15-year-old girl in the U.S. With a waistline measuring 30.4 inches, she fits around a size 10 according to ASTM standards.

While it’s unlikely that clothing designed for adults will fit a teen’s body perfectly, she has quite a few sizing options.

However as she’ll quickly learn, sizes are not universal across all brands. Here are all the sizes within 1 inch of the median teen’s waistline.

At Reformation, she’s closer to a size 8. At Uniqlo, she’s considered a size 12.

The median adult woman has a much harder time finding clothes that fit. Her waistline is 37.68 inches, placing her at a size 18 by ASTM standards.

Many brands don’t carry her size. This is especially true for high-end, luxury fashion labels.

Sizing issues are amplified even further within Plus size ranges. Some Plus sizes start at size 12, others at 18. Others still consider any size from 00 to 30 as part of their Regular line.

The median adult woman may also find herself in what’s informally called the “mid-size gap,” seen here in Anthropologie’s size chart.

Sizes within the Regular size range are too small, yet the next size up in the Plus range might be too big.

Even the symbols used to describe certain sizes hold a wide range of meanings.

For the average adult woman, there are as many as 10 different ways to describe the garments that she could conceivably wear from these brands alone. At Reformation she’s closer to a size 14. At Shein, she’s a 2XL in their plus size range.

Explore more

Interact with the dots for more information about each brand and size.

The villain arc of

On top of all these problems, consumers often know the labels for any given size cannot be trusted.

Vanity sizing, the practice where size labels stay the same even as the underlying measurements frequently become larger, is so ubiquitous across the fashion and apparel industry that younger generations have never experienced a world without it.

Cultural narratives around vanity sizing often square the blame on female shoppers, not brands. Newsweek once called it “self-delusion on a mass scale” because women were more likely to buy items that were labeled as sizes smaller than reality. But there’s more to the story.

Vanity sizing provides a powerful marketing strategy for brands. Companies found that whenever women needed a size larger than expected, they were less likely to follow through on their purchases. Some could even develop negative associations with the brand and never shop there again. But when manufacturers manipulated sizing labels, leading to a more positive customer experience, brands could maintain a slight competitive edge.

The dynamic perpetuates an arms race toward artificially deflating size labels. Most shoppers aren’t even aware when size charts change, or by how much. If anything, vanity sizing consistently gaslights women to the point where few are able to know their “true” size. But where would we be today without it?

1995 sizes

Waistline in Inches

2021 sizes

It’s true: Sizes today are much larger than they were in the past.

Roughly 30 years ago, ASTM guidelines covered waistlines between 24 and 36.5 inches, representing a 12.5-inch spread from size 2–20. (While extended sizes technically existed at the time, they were not widely available in stores).

In the early 2000s ASTM added size 00 and 0 to pad out the bottom of the range.

Today, because of vanity sizing, we can see an upward shift in all sizes. ASTM guidelines span 15.12 inches from 25.38–40.5 inches for sizes 00–20.

By comparison, today’s size 8 is 2.5 inches larger in the waist than it was 30 years ago.

But vanity sizing didn’t just account for women’s unconscious shopping behaviors. Clothes needed to be larger because our waistlines had grown.

The average woman’s waistline today is nearly 4 inches wider than it was in the mid-1990s.

Here’s the surprising silver lining to vanity sizing: Over this 30-year period, the median adult woman has almost always fit the size 18 that was available to her at the time.

Vanity sizing has effectively helped manufacturers keep up to pace with demographic shifts in the U.S. But only for the smallest half of all adult women.

Explore more

Interact with the dress forms to see how sizes changed from 1995 to 2021.

I once believed that change was inevitable and sizing problems would become a relic of the past. If it wasn’t some scrappy upstart that promised to revolutionize the sizing system, then at least the major fashion conglomerates would be well-placed to modernize and tap the full potential of the plus-size market. But that progress never fully materialized. And I got tired of waiting.

A few years ago, I started learning how to sew. Somehow it felt more practical to make my own clothes than count on meaningful change to happen on its own. Getting started was easier than I thought. The first sewing pattern I ever completed — a boxy, drop-shoulder style that could turn into either a shirt or dress — was free to download. It included a 29-page instruction manual with photos and illustrations documenting every step.

a sketch of a bodice block on grid paper with a ruler and notebook

Drafting a custom pattern based on my body measurements and proportions

From there, I started learning how to draft my own sewing patterns from scratch. That’s when I realized the truth behind my sizing struggles: Clothing sizes are optimized for mass production and appeal — not women’s bodies. Nothing represents this more than a size 8.

Fashion designers often use body measurements for a size 8 as a starting point when creating new design samples. Manufacturers then use a mathematical formula to determine each next size up or down the range in a process called grading. The effect is like a Russian doll. Each size up is incrementally larger than the last.

The uniform shape makes it easier for factories to mass-produce garments, however it comes with several tradeoffs. It’s hard to scale up to larger-sized clothing before the proportions become distorted. It also becomes impractical to make multiple versions of a single item to accommodate varying body shapes or heights. That means most women’s clothing is derived from a single set of proportions — a size 8. According to U.S. health data, fewer than 10% of adult women have waistlines that fit the standard sample size or smaller.

I, like the vast majority of women, do not fit the standard mold. Instead I took an old pattern-making textbook often taught in fashion design schools to start making clothes to fit my own unique proportions. I gathered and recorded over 58 different body measurements in order to get started and from there, I could make my own custom base pattern, known as a bodice block or sloper.

Standard bodice block

My bodice block

Once I compared my personalized sloper to commercial patterns and retail garments, I had a revelation: clothes were never made to fit bodies like mine. It didn’t matter how much weight I gained or lost, whether I contorted my body or tried to buy my way into styles that “flatter” my silhouette, there was no chance that clothes would ever fit perfectly on their own. Finally I understood why.

Inverted Triangle

Top Hourglass

Oval

Rectangle

Hourglass

Diamond

Triangle

Bottom Hourglass

Spoon

As women, it’s drilled into our heads that the ideal body type is the hourglass: wide shoulders and hips and a snatched waist.

But that’s an unrealistic standard for most people.

Researchers have identified as many as nine different categories of body proportions commonly found among adult women alone. Many are likely familiar to those told over the years to “dress for their body type.”

Most women do not have an exaggerated hourglass silhouette, instead the median woman is shaped more like a rectangle.

That’s because age and race factor heavily into how our bodies are shaped. Genetics can influence everything from a person's proportions to how they build muscle mass to where their bodies tend to store fat.

One 2007 study found that half of women (49%) in the U.S. were considered rectangle-shaped. Only 12% of women had a true hourglass figure.

While the U.S. does not track bust measurements,* we know that the median woman's waist-to-hip difference is roughly half that of 'ideal' hourglass proportions.

Still, size charts continue to champion a defined waistline as the sole foundation to most women’s apparel.

For example, here’s J.Crew’s size chart. They use a rigid set of dimensions, where the waist measurement is exactly 10 inches smaller than the hip for all sizes.

That means the smallest and largest sizes in a range will have the exact same body shape.

Actual bodies, however, are far less uniform or symmetrical.

A size 18 pair of pants from J.Crew might fit the median woman’s waist, but they’d likely be too large in the hips by at least 6 inches.

Conversely a size 12 would fit her hips best, but it’s unlikely that she’d be able to squeeze into a waistband that’s 6 inches smaller than her own.

Of course, J. Crew isn’t the only brand whose size chart is distorted. It’s the industry standard.

Out of these 15 brands, only H&M comes close to the median woman’s shape, especially as sizes get bigger.

Explore more

Use the selector in the top left corner, to highlight a size.

sizing for

The fashion industry thrives on exclusivity. Luxury brands maintain their status by limiting who is able to buy or even wear their clothes. If few women fit the “ideal” standards, then products serving only them are inherently exclusionary. Size charts become the de facto dividing line determining who belongs and who doesn’t.

This line of gatekeeping is baked into the foundation of virtually all clothing. The modern sizing system in the U.S. was developed in the 1940s based on mostly young, white women. No women of color were originally included. The system was never built to include a diverse cross-section of people, ages, or body types. It has largely stayed that way by design.

In its 1995 standards update, ASTM International admitted that its sizing guidelines were never meant to represent the population at large. Instead body measurements were based on “designer experience” and “market observations.” The goal was to tailor sizes to the existing customer base. But what happens when more than half of all women are pushed to the margins or left behind?

It doesn’t have to be this way. Teenage girls shouldn’t be aging out of sizing options from the moment they start wearing women’s clothes. A woman does not need hourglass proportions to look good, just as garment-makers do not need standardized sizes to produce well-fitting clothes.

There are no rules forcing brands to adopt any particular sizing system. There is no such thing as a “true” size 8, or any size for that matter. If brands are constantly developing and customizing their size charts, then it makes little sense to perpetuate a broken system. Sizes are all made up anyway — why can’t we make them better?

Methodology

To highlight the median body proportions of the adult women in the U.S., we relied on anthropometric reference data for children and adults that is regularly released by the National Center for Health Statistics within the U.S. Department of Health and Human Services.

For this story, we pulled data on the median waistline circumference of women and girls that was gathered between 2021-2023. For girls and women under 20 years old, measurements were recorded in two-year age ranges (ex: 10–11 years, 14–15 years), with a median of 141 participants per age range. For women over 20, measurements were recorded in nine-year age ranges (ex: 20–29 years, 30–39 years) and collectively for all women 20 and older. Each nine-year age range had a median of 465 participants. Overall, measurements were recorded for 3,121 women ages 20 and older. Those who were pregnant were excluded from the data.

HHS also provides a breakdown of measurements within set percentiles for each age range, which includes figures for the 5th, 10th, 15th, 25th, 50th, 75th, 85th, 90th, and 95th percentiles. We then used that percentile data to extrapolate the waistline measurements of all women and girls within each respective age group.

We also compared figures to those recorded by HHS from 1988-1994. There, 7,410 women ages 20 and older participated in the study. Measurements were originally recorded in centimeters, so we converted to inches.

Brands included in the size chart comparisons represent a diverse cross-section of popular apparel brands and retailers in the U.S., including a mix of mass market, fast fashion, premium and luxury labels.

For each brand, we focused on collecting body measurements for “regular” or “standard” size ranges, as well as “plus” sizes when available. Sizing information for “petite,” “tall,” or “curve” clothing lines were not included. Size charts reflect the body measurements for garments categorized as general “apparel.” In a select few cases where that category was unavailable, “dresses” were used as the default garment type.

Within each size range, we focused on collecting three main body measurements: Bust, waist, and hip. Some were presented as a range from minimum to maximum values, while others were single measurements. All numeric U.S. women’s sizing labels and descriptions were recorded, as well as their corresponding alpha sizes, when available.

Size chart data was last manually captured in July 2025 and may not reflect a brand’s current size chart. Brands frequently change their size charts, and more often than not, shoppers aren’t even aware when measurements or sizes are updated.

The standardized size charts refer to ASTM International’s regular release of its Standard Table of Measurements for Adult Female Misses Figure Type. The 1995 release (designated as D 5585-95) reflects sizes 2-20. ASTM updated its standards in 2021 (designated as D5585-21) to include sizes 00-20.

Ransom note letters are from Indieground.

Related pieces