A casual comment by a student alerted the authors to the existence and prevalence of Internet-based paraphrasing tools. A subsequent quick Google search highlighted the broad range and availability of online paraphrasing tools which offer free ‘services’ to paraphrase large sections of text ranging from sentences, paragraphs, whole articles, book chapters or previously written assignments. The ease of access to online paraphrasing tools provides the potential for students to submit work they have not directly written themselves, or in the case of academics and other authors, to rewrite previously published materials to sidestep self-plagiarism. Students placing trust in online paraphrasing tools as an easy way of complying with the requirement for originality in submissions are at risk in terms of the quality of the output generated and possibly of not achieving the learning outcomes as they may not fully understand the information they have compiled. There are further risks relating to the legitimacy of the outputs in terms of academic integrity and plagiarism. The purpose of this paper is to highlight the existence, development, use and detection of use of Internet based paraphrasing tools. To demonstrate the dangers in using paraphrasing tools an experiment was conducted using some easily accessible Internet-based paraphrasing tools to process part of an existing publication. Two sites are compared to demonstrate the types of differences that exist in the quality of the output from certain paraphrasing algorithms, and the present poor performance of online originality checking services such as Turnitin® to identify and link material processed via machine based paraphrasing tools. The implications for student skills in paraphrasing, academic integrity and the clues to assist staff in identifying the use of online paraphrasing tools are discussed.