AI Humanizer BenchmarkLeaderboard / Compare / SmartHumanizer vs UndetectedGPT
Head to head · September 2026 cycle
SmartHumanizer vs UndetectedGPT
UndetectedGPT finished 0.1 points ahead of SmartHumanizer in the September 2026 cycle, 84.90 to 84.80, ranking #1 against #2 in a field of 11. UndetectedGPT scored higher on 6 of 7 detectors and 4 of 7 writing categories. SmartHumanizer came out ahead on Meaning preservation (87.6 vs 84.8), QuillBot (94.2 vs 92.7), Blog post (82.4 vs 77.6). The bypass-rate gap, 85.3 to 86.3, sits inside both tools' 95% confidence intervals, so treat bypass as a draw.
- Detectors
- 1 – 6
- Categories
- 3 – 4
- Components
- 1 – 3
- Last tested
- 2026-09-03
- Prompts
- 33
- Methodology
- v1.0.0
Score components
What the overall score is made of: bypass rate weighs 42%, meaning preservation 32%, readability 16%, consistency across categories 10%. Output-quality penalties come off the total. How scoring works
CIs overlap marks a gap that sits inside both tools' 95% confidence intervals for bypass rate; it may not survive another cycle.
Detector by detector
Share of each tool's outputs that a detector classified as human-written. UndetectedGPT took 6 of 7.
Writing categories
Category score per writing context: bypass credit only for real rewrites, blended with the category's own meaning preservation and readability. Small categories swing; the prompt count is shown on each row.
Where each one wins
Every measure above that one tool won outright, largest margin first within each group.
SmartHumanizer
5 wins- Meaning preservation Score87.6 vs 84.8
- QuillBot Detector94.2 vs 92.7
- Blog post Category82.4 vs 77.6
- Marketing copy Category89.2 vs 85.8
- Academic essay Category89.8 vs 89.2
UndetectedGPT
13 wins- Consistency Score91.5 vs 88.3
- Readability Score77.3 vs 75.7
- Bypass rate Score86.3 vs 85.3
- GPTZero Detector80.0 vs 71.0
- Copyleaks Detector21.2 vs 15.2
- Winston AI Detector54.4 vs 51.0
- ZeroGPT Detector85.1 vs 82.6
- Grammarly Detector89.3 vs 86.9
- Originality.ai Detector79.2 vs 78.2
- News article Category85.9 vs 79.3
- Business email Category79.7 vs 75.6
- Application essay Category86.2 vs 83.3
- Discussion board Category90.3 vs 88.3
Questions people ask
Is SmartHumanizer better than UndetectedGPT?
UndetectedGPT finished 0.1 points ahead of SmartHumanizer in the September 2026 cycle, 84.90 to 84.80, ranking #1 against #2 in a field of 11. UndetectedGPT scored higher on 6 of 7 detectors and 4 of 7 writing categories. Both tools ran the same 33 prompts, scored by the same 7 detectors, under methodology v1.0.0; every input, output, and verdict is published.
Which bypasses AI detectors better, SmartHumanizer or UndetectedGPT?
UndetectedGPT posted the higher bypass rate, 86.3 vs 85.3, and scored higher on 6 of 7 detectors. SmartHumanizer led on QuillBot; UndetectedGPT led on GPTZero, Winston AI, Originality.ai, ZeroGPT, Grammarly and Copyleaks. The overall bypass gap is inside both 95% confidence intervals, so it is not a reliable difference.
Do SmartHumanizer and UndetectedGPT keep the original meaning?
SmartHumanizer preserved meaning better, 87.6 vs 84.8 on our 0–100 similarity scale. On readability, UndetectedGPT rated higher, 77.3 vs 75.7. Penalties this cycle: SmartHumanizer None, UndetectedGPT None.