I tested 10 AI content detectors - and these 5 correctly identified AI text every time

When I first examined whether it's possible to fight back against AI-generated plagiarism and how that approach might work, it was January 2023 -- just a few months into the world's exploding awareness of generative AI.

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This is a completely updated version of that original January 2023 article. When I first tested GPT detectors, the best result was 66% correct from one of three available checkers. My most recent set of tests, in February 2025, used up to 10 checkers -- and three of them had perfect scores. This time, just a couple of months later, five did.

What I'm testing for and how I'm doing it

Before I go on, though, let's discuss plagiarism and how it relates to our problem. Merriam-Webster defines "plagiarize" as ...