Is Grammarly’s Plagiarism Checker Actually Accurate?

Many teachers use Grammarly already, and its built-in plagiarism checker seems like a convenient bonus. But how accurate is it really? I did some testing.

For detecting copy-paste plagiarism from web sources, Grammarly performs well. When I pasted text directly from Wikipedia articles, news sites, and publicly available essays, Grammarly caught it consistently and identified the source. This is its strength.

For detecting paraphrased plagiarism (where a student rewrites a source in their own words without attribution), results were mixed. Grammarly caught close paraphrases but missed more distant rewrites. This is expected, as paraphrase detection is harder for all plagiarism tools.

For cross-checking against academic databases and student submissions, Grammarly falls short of Turnitin. It doesn’t have access to the same repository of academic papers and institutional submission databases. If a student copies from a published journal article or from another student’s previously submitted paper, Grammarly is less likely to catch it.

For AI-generated content, Grammarly’s plagiarism checker doesn’t specifically detect AI text. It would only flag AI content if that exact text appeared elsewhere on the web, which is unlikely since AI generates unique text each time.

Is it accurate for what it does? Yes. Is it sufficient as your only plagiarism tool? Probably not if academic integrity is a serious concern at your school. Think of it as a first line of defense that catches the obvious cases, supplemented by more robust tools for thorough checking.

The convenience factor is real though. Having plagiarism checking integrated into the tool you’re already using for grammar means you’re more likely to actually use it regularly. Consistent basic checking is better than inconsistent comprehensive checking.

What’s been your experience with Grammarly’s plagiarism detection?