AI Detector Performance Comparison Table
| Actual AI % | Ahrefs | Copyleaks | GPTZero | Originality.ai | Scribbr | ZeroGPT | Grammarly | Writer |
|---|---|---|---|---|---|---|---|---|
| 100% | 100% | 100% | 92% | 100% | 94% | 99.62% | 59% | 24% |
| 100% | 100% | 100% | 100% | 100% | 100% | 98.99% | 57% | 23% |
| 100% | 86% | 83.8% | 52% | 64% | 0% | 67.76% | 7% | 15% |
| 0% | 2% | 0% | 0% | 0% | 0% | 0% | 0% | 2% |
| 0% | 6% | 0% | 0% | 0% | 0% | 2.76% | 0% | 2% |
| 0% | 0% | 0% | 4% | 0% | 0% | 91.69% | 0% | 27% |
| 50% | 13% | 46.4% | 42% | 46% | 0% | 39.06% | 0% | 0% |
| 50% | 32% | 0% | 28% | 4% | 0% | 29.4% | 0% | 5% |
| 50% | 70% | 100% | 86% | 4% | 83% | 83.21% | 0% | 6% |
| Total Score | 13 | 13 | 12 | 12 | 10 | 9 | 6 | 4 |
AI Detector Summary Table
| AI Detector | Score (Out of 18) | URL | Performance Summary |
|---|---|---|---|
| Ahrefs | 13/18 | https://ahrefs.com/writing-tools/ai-content-detector | Highly accurate with zero false positives on human content; strong model detection (GPT-4o, Llama). Minor difficulty with hybrid content. |
| Copyleaks | 13/18 | https://copyleaks.com/ai-content-detector | Excellent at clear AI detection; slightly inconsistent on mixed content. |
| GPTZero | 12/18 | https://gptzero.me | Strong at identifying high-AI content; less confident on hybrid or borderline sections. |
| Originality.ai | 12/18 | https://originality.ai/ai-checker | Good for AI-heavy text; sometimes overestimates human writing when AI is subtle. |
| Scribbr | 10/18 | https://www.scribbr.com/ai-detector/ | Decent for obvious AI but inconsistent for nuanced writing. |
| ZeroGPT | 9/18 | https://zerogpt.com | Accurate in extreme cases; unreliable on partial-AI content. |
| Grammarly | 6/18 | https://www.grammarly.com/ai-detector | Low confidence and frequent misclassification; struggles with clear AI signals. |
| Writer | 4/18 | https://writer.com/ai-content-detector/ | Weakest performer with frequent misses and poor detection accuracy. |
AI Detector Feature Comparison
| Detector | Strengths | Weaknesses |
|---|---|---|
| Ahrefs | Model detection (GPT-4o, Llama), strong accuracy, integrated SEO insights, no false positives | Struggles with heavily blended human+AI content |
| Copyleaks | Great at clear AI content, high precision | Mixed/hybrid content may reduce accuracy |
| GPTZero | Very reliable for high-AI text | Hesitates on borderline or edited AI content |
| Originality.ai | Accurate for heavy AI sections | May overestimate human authorship |
| Scribbr | Good with obvious AI patterns | Inconsistent with nuanced content |
| ZeroGPT | Strong at extremes | Often inaccurate with partial-AI text |
| Grammarly | Easy to use | Low detection accuracy |
| Writer | Fast, simple interface | Lowest precision overall |
