If statistics (and marketing) are to be believed, most of us women are walking around wearing bras that do not fit us properly. Straps are digging into our shoulders; under-wires are compressing our ribs; our cups runneth over.

Last week, Mallory Ortberg, founder of the website The Toast, published a satirical account of her own bra-size epiphany, on the very day another author published an earnest one. Also that day, large-busted models made a rare appearance on Vogue.com, in a photo shoot by renowned photographer Cass Bird. In the feature, entitled “’Give me a D! Give me an F!’ Because Gorgeous Bras Come in All Shapes and Sizes,” photos were captioned with models’ quotes about well-fitting bras, and how difficult it is to find them.

This storyline isn’t new. (“Women of America,” Oprah declared, on her 2005 “Bra Revolution” episode, “you need to rise up and get a proper bra fitting.”) But today the movement has new fervor, with blogs such as Busts4Justice and Sweet Nothings reviewing the support, or lack thereof, provided by underpinnings and the companies that manufacture them.

Those companies are wise to pay attention. In 2013, lingerie sales were worth nearly $12 billion in the US alone. A spate of startups is out to “disrupt” what arguably is a broken system, and pick up the pieces—and profits.

In 2013, lingerie sales were worth nearly $12 billion in the US alone.

Perhaps one of the shrewdest founders in the field is Michelle Lam, whose San Francisco-based online lingerie company, True&Co., draws on her professional experience in data science and investing at Bain Capital and the Boston Consulting Group, and also her personal experience in bra shopping.

True&Co. offers a Warby Parker-style “try before you buy” model and invites women to answer a series of questions about the bras they receive: Is the band too tight or too loose? The cup too small or too big? Is the lift too padded? Not padded enough? How about the color? Also…are you married?

“One third of the data points we gather have nothing to do with bras,” says Lam. “Women in a relationship are buying less red lacy underthings than women who are single.”

True&Co. Special delivery.

Since True&Co.’s 2012 launch, more than 1 million women have taken the site’s “fit quiz.” The results place each woman into a color on the company’s proprietary fit spectrum, based on the shape and size of her breasts.

True&Co. Don’t be sad if you’re shallow.

If you’ve never considered whether your breasts are rounder on the top, bottom, or sides, this would be the time. Once you’ve taken the quiz and been assigned a color—“sapphire,” for example, indicates a shape that’s shallow and bottom-heavy—an algorithm recommends an assortment of bras.

In October 2013, the algorithm started to serve up not only popular brands such as Calvin Klein and Natori, but also True&Co.’s own private-label collections. Within a few months of True&Co.’s launching its second collection, Uniform, in June, revenue from the private label accounted for 20% of sales. Lam predicts it will be 40% by the end of the year.

“Nips are probably not great in a coed board meeting situation—in the American landscape anyway.”—Michelle Lam

True&Co. says the recommendation algorithm is brand-agnostic, but what potentially separates the brand’s own bras from, say, Calvin Klein’s, are designs that benefit from data and feedback the company receives from customers. And more bras sold means more data gathered: True&Co. reports that 7 million points of “boob data” have grown to 22 million within the last three months alone.

So what does all this data yield?

For one thing, padding. Lam says one of the most common issues for her customers is “nipple modesty,” meaning that women don’t want the silhouette of their nipples to be visible through their shirts. So for True&Co.’s latest collection of lace bras, Lam was mindful that the pieces include a substantial lining.

True&Co.

“It gives you the nipple modesty to get you through the day, because nips are probably not great in a coed board meeting situation—in the American landscape anyway,” says Lam.

True&Co. sent me a sample of its best-selling bra, a push-up model from its own private label. It holds its shape like an egg crate and has what Lam calls a “banana pad,” a crescent-shaped cushion that runs along the bottom and widens at the outer edges of the cups.

“The banana pad was based on the number of women who reported they were not only shallow breasted—especially after having children—but that also their cup gaped at the top, meaning that the cup was too big for their breast,” Lam explains.

“This was a predominant issue especially among smaller cup sizes, so we took this banana pad—which not only lifts the flesh in from the bottom and gives you lift there—but also flesh in from the sides, so it creates a super-subtle, fill-up-the-cup type look without being a super push-up look,” Lam says, “because we also know from our quiz that four in five women didn’t want an extreme pushup.”

Personally, I found the bra to be overly padded and structured. But as it turns out, Lam might have predicted that, too. The thin, unlined style of bras I prefer are popular with “a sliver of women in New York and San Francisco,” of which I am apparently one.

I took the fit quiz and tried out the service myself, ordering five bras from those selected for me by True&Co.’s algorithm. A few days later, I opened the box at home, and opened my laptop. A checklist of the bras in the box appeared on my True&Co. account page, each with the option to “keep” or “return.” But before I could return anything, I had to select a reason, whether it involved the band, cup, lift, or color.

True&Co. makes the process relatively simple, with free shipping and returns via a label included in the original package. But procrastinators beware. Understandably, True&Co. doesn’t want its inventory just hanging around customers’ homes: If I failed to fill out the form and get the box postmarked back within five days, I would be charged a $20 fee. After 30 days, I would be charged for the contents of the box in full.

The most promising bras I tried were evenly split between True&Co.’s private label and another brand selling at a comparable price point. I’m not sure whether I’ll go back for round two, but it’s possible I will because at this point, I’ve invested some time in the process. It’s as if I’m already in the dressing room, and a store attendant has offered to grab something in another size.

I didn’t find a bra I loved in that first box. But in ticking the reasons why each wasn’t quite right, and even adding a sentence or two of free-form feedback, I gave True&Co. the ammo to recommend another round of options—while adding to the company’s ever-increasing pool of data.