Tired of walking out of stores with yet another uncomfortable, ill-fitting bra, former Google exec Heidi Zak decided to take matters into her own hands. In 2013 she and her husband, David Spector, launched direct-to-consumer bra company ThirdLove. Their secret: using data to find a woman's perfect measurement.

Zak claims that standard industry measurements don't work for all women.

"One of the things that we found in the early days of ThirdLove was that traditional sizes didn't work for everyone. I'm personally a half size. A lot of women were falling in between traditional cuts — A and B, B and C. So we created half sizes."

Today ThirdLove produces 70 sizes, 40 more than traditional brands. The underpinnings for their success is the company's Fit Finder technology, a 60-second quiz that asks women questions to determine their bra size. Over 11 million women have used it.

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"Traditiona retail in part, why it's so broken today, is because of the lack of data in everyday decision-making. ... We use data in everything we do through our Fit Finder. Over 11 million women have used it. We use the data for marketing, personalization, product delivery, inventory planning, almost everything."