Software testing is an integral part of software development that provides better quality products and user experiences and helps build the reputation of software companies. Though software testers perform a role that requires specific tasks and skills, in-depth studies of software testers lag behind research studies of other roles within software development teams. In this paper, we aim to create a profile of testers by presenting an empirical analysis of the skills the industry currently needs. We analysed data from 400 job ads in 33 countries. We mapped the skills on a taxonomy comprising test-related, technical, and domain-specific skills. In addition, we looked at the demand for educational attainment, relevant certifications, and previous experience requirements. Our findings show that employers are mostly interested in skills related to test planning and design, test automation, functional testing, performance testing, and progress reporting. One third of the job advertisers were interested in people with the skills to operate test execution tools. Selenium was the testing tool most in demand. The testers must have strong technical abilities, including programming skills in Java, C#, and SQL. Also, they must handle project management tasks such as estimation, risk management, and quality assurance. Employers do not emphasise domain-specific knowledge, which indicates that they consider testing skills portable across industries. One in seven job ads asks for a software testing certification. Our study helps clarify the complexity of the testing job and outlines the capabilities one needs to fulfil a software tester's responsibilities.