As of 2015, women's apparel ranks as the best-selling standalone item online, according to StatisticBrain.com. Books come in at number two, followed by computer hardware and computer software in third and fourth place, respectively.
The best-selling cluster of items online are software, books, music and flowers, advises StatisticBrain.com. The group of four items accounts for 26% of all annual Internet sales, with sales totalling $37.05 billion. Computer hardware, consumer electronics and office supplies combine to account for 16% of online sales, totalling $22.8 billion in sales annually. In third place is the category of apparel, footwear, jewelry, linens and home decor; this group garners 13% of the online market share and brings in approximately $26 billion annually.