Scopus is described as 'Elsevier’s Scopus, the largest abstract and citation database of peer-reviewed literature. Search and access research from the science, technology, medicine, social sciences and arts and humanities fields' and is a academic research tool in the education & reference category. There are more than 10 alternatives to Scopus, not only websites but also apps for SaaS, Mac, Windows and Linux. The best Scopus alternative is Google Scholar, which is free. Other great sites and apps similar to Scopus are Connected Papers, Elicit, Scinapse and Snowball.
Google Scholar includes questionable sources