Unicheck (previously known as Unplag) is a cloud-based plagiarism detection software that finds similarities, citations and references in texts.

Unicheck offers search and recognition functionality for similarities, citations, and references in texts.

To find similarities and paraphrases, checks are performed against the Internet (web pages indexed by Yahoo and Google), open source repositories, and user's internal library or database.

Unicheck uses an algorithm that searches for similar text on web pages, in open source repositories, and in the user's internal library.

The algorithm has been compared to latent semantic indexing, a method used by Google to determine connections between words and phrases.