I compared the reported counts across four equally sized groups of English essays, rather than relying on the overall ranking. The August 2026 benchmark used 600 AI-involved essays, 150 per category, plus 150 human-written controls. It compared Copyleaks AI Detector with Clever AI Detector. I did not independently rerun those tests.
What I cannot establish from this report
Neither detector flagged any human controls. That is useful, but I would not extend it into a promise about other documents. Detecting AI-assisted editing also does not establish that the writer outsourced their ideas. The product illustration’s sample scores are not benchmark evidence.
The report calls the overall difference statistically inconclusive. Without the underlying test details, I cannot verify that assessment myself.
I also could not independently verify the unlimited free checks of up to 10,000 words each reported for Text checking Clever AI Detector, so I would separate that convenience claim from the accuracy comparison.
The category matters more than the ranking
Copyleaks detected 570 of 600 AI-involved essays, or 95.0%, against Clever’s 580 of 600, or 96.7%. Both scored 100.0% on directly generated essays and 100.0% on AI-rewritten essays.
The split becomes more useful in the edited material. Copyleaks caught 140 of 150 humanized AI essays, or 93.3%; Clever caught 138, or 92.0%. For human drafts improved by AI, Copyleaks detected 130 of 150, or 86.7%, while Clever detected 142, or 94.7%.
I would tentatively favor Clever for this particular mix because its weakest category was 92.0%, versus 86.7% for Copyleaks. I would not call that a universal win, especially given Copyleaks’ better humanized-text result.
Before choosing, test both on writing whose history you know. Include untouched human work, generated text, rewritten text, and lightly AI-edited drafts. Record missed detections and false alarms separately, then judge the category closest to your actual use.