In recent years, the rapid development of blockchain technologies have attracted worldwide attention. Its application has been extended to many fields, such as digital finance, supply chain management, and digital asset transactions. For some enterprises and users, how to choose the most effective platform from many blockchains to control costs and share data is an important issue. To comprehensively evaluate the blockchain technologies, we first construct three-level evaluation indicators in terms of technical, market, and popularity indicators. Then, we propose an improved global DEA-Malmquist index without explicit inputs to assess the dynamic performance of blockchain technologies. Finally, we carry out an empirical analysis to evaluate 31 public blockchains' performance from May 2018 to April 2020. The results indicate that the overall performance of blockchain technologies is basically on the rise. Some blockchain technologies that have not yet received widespread attention have shown good dynamic performance.