The RealReal, a luxury consignment e-commerce venue, this week announced the launch of RealBook, a Kelley Blue Book-type app, that allows consumers and consignors to calculate the resale value of products in categories such as women’s and men’s fashion, and fine jewelry and watches. The company said RealBook can be used as a predictive tool by shoppers buying at retail to assesses the future value of designer items they are buying.

The app allows consumers to view and sort thousands of products by resale price, save products under “favorites” to get resale price updates, share products via text, Facebook, Twitter and e-mail, and shop similar products on The RealReal.

The RealBook app is fed by proprietary data aggregated from The RealReal’s database of more than 500 designer brands and 500,000 luxury goods sold to date. An example of resale value data for luxury designers from the RealBook app include the resale value of popular brands. For example, David Yurman is 45 percent off retail, Hermès accessories, 30 percent and Jimmy Choo, 65 percent.

Brands that hold their value the longest include Cartier, Chanel, Christian Louboutin, David Yurman and Van Cleef & Arpels. Brands that lose their value the quickest include Valextra, Tod’s, Versace and Etro. 

“Over the last couple years, we’ve seen our consignors turn into savvy shoppers, calling us on a daily basis from retail stores, asking what designer brands they should buy to get the highest resale value in the future,” said Julie Wainwright, founder and chief executive officer of The RealReal. “We realized this was becoming a trend and built RealBook to inform and empower consumers with data to help them manage and make smart luxury investments.”

The RealReal has more than three million members who sell luxury items to the site. According to the company, it’s the largest marketplace of designer brands such as Chanel and Louis Vuitton. The RealReal, which launched three years ago, processes more than 40,000 luxury goods per month and has shipped more than 500,000 luxury items to date. “The RealReal is changing the way people think about luxury shopping and consignment,” Wainwright said.