According to Tracy DiNunzio, the average woman has only worn about 20 percent of her wardrobe in the past year.
That stat is at the heart of Tradesy.com, the company DiNunzio started back in 2012. Tradesy.com, an online consignment shop and marketplace, is built on the idea that you can turn the other 80 percent of the items in your closet into cash.
In an interview on CNBC's On The Money, DiNunzio said her company is similar to eBay, but has a distinct advantage the online auction giant does not.
"EBay serves 14 major categories with the same kind of platform," DiNunzio explained. "Because we're only in fashion, we've been able to tailor our service to make it quick, easy and valuable for our sellers."
At brick-and-mortar-consignment shops, "you only make about 40 percent of the sale," DiNunzio said. Yet with Tradesy, "you pay a 9 percent commission, and keep 91 percent of the sale."
After signing up on the site, users post a picture of an item and set a price. If someone buys it, Tradesy will send the user a free mailing kit.