Alibaba Group Holding Ltd said on Thursday that it has attracted over 100 million business-to-business customers, making the e-commerce giant the world's top B2B online service provider.

After 15 years of development, the number of registered merchants on 1688.com, Alibaba’s B2B unit, doubled to 100 million in less than two years, the company said in a statement.

The climax of daily sales rocketed to 290 million yuan ($47.3 million) during a recent wholesale promotion in May, tripling the transaction amount of its B2C counterpart Tmall.