Quality-of-Service (QoS) is widely employed for describing non-functional characteristics of Web services. Although QoS of Web services has been investigated intensively in the field of service computing, there is a lack of real-world Web service QoS datasets for validating various QoS-based techniques and models. To investigate QoS of real-world Web services and to provide reusable research datasets for future research, we conduct several large-scale evaluations on real-world Web services. Firstly, addresses of 21,358 Web services are obtained from the Internet. Then, three large-scale real-world evaluations are conducted. In our evaluations, more than 30 million real-world Web service invocations are conducted on Web services in more than 80 countries by users from more than 30 counties. Detailed evaluation results are presented in this paper and comprehensive Web service QoS datasets are publicly released online.