Some well-known duplicate checking systems, such as HowNet, Wanfang, Weipu and paperFree and papertime of paper series, have wide duplicate checking accuracy and coverage, and are suitable for various disciplines, among which the duplicate checking systems of paperfree and papertime are more affordable. In addition, some specialized discipline duplicate checking systems, such as medical associations and farmers' associations, are relatively low in price, but their detection accuracy and coverage may be limited, and they are only suitable for papers in corresponding disciplines.
When choosing a duplicate checking system, it is recommended to know your own needs and budget first, and comprehensively consider the factors such as price, accuracy, coverage and safety, and choose a duplicate checking system and service that suits you. At the same time, we should also pay attention to protecting personal privacy and academic integrity, and avoid using unsafe duplicate checking services or copying other people's papers.