Copyleaks is a Generative AI Detector built into Imagine Learning. As of 2025, it is the market's most comprehensive and accurate tool. Not only does the tool look for general plagiarism, but it also does a fantastic job of identifying content written by popular AI tools that students use to take shortcuts on assignments.
Imagine Learning has an article on the Help Center that explains how the tool works and how best to use it to help you as an instructor.
If the assignment shows the scan option, use it. Be aware that the tool requires a minimum of 10 words for the scanner to run. If the student submits anything less than that, the scan will not be completed. The tool is more accurate if the submission is 400 words or more. If a student uploads an assignment and has been flagged in the past for using AI, you may use the trial version of Copyleaks to scan that assignment. The tool does not take into account whether a student cited a source. That is why you should always open and review each report.