Skip to content
The September 2026 results are in: WriteHuman holds #1, and newcomer SupWriter debuts at #5.Read the full analysis →
HumanizerBench

Head to head · September 2026 cycle

Humanize AI Pro vs Undetectable.ai

Undetectable.ai finished 1.7 points ahead of Humanize AI Pro in the September 2026 cycle, 71.75 to 70.07, ranking #6 against #7 in a field of 14. Undetectable.ai scored higher on 5 of 5 detectors and 4 of 7 writing categories. Humanize AI Pro came out ahead on penalties (None vs −6.0), blog post prompts (76.0 vs 57.5) and news article prompts (66.8 vs 51.8). The bypass-rate gap, 70.8 to 82.1, sits inside both tools' 95% confidence intervals, so treat bypass as a draw.

70.07 /100
overall score
#7 /14
rank ▼ 5
+1.68
Undetectable.ai leads →
Detectors
0 5
Categories
3 4
Components
2 3
71.75 /100
overall score
#6 /14
rank ▲ 2
Last tested
Prompts
33
Methodology
v1.2.0

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 →

Bypass rate CIs overlap Undetectable.ai by 11.3
70.8 82.1
Meaning preservation Undetectable.ai by 7.4
74.7 82.1
Readability Humanize AI Pro by 0.1
61.8 61.7
Consistency Undetectable.ai by 5.8
65.3 71.1
Penalties fewer is better Humanize AI Pro by 6.0
None −6.0

CIs overlap marks a gap that sits inside both tools' published 95% confidence intervals for that component; it may not survive another cycle.

Detector by detector

Share of each tool's outputs that a detector classified as human-written. Undetectable.ai took 5 of 5.

GPTZero Undetectable.ai by 14.0
58.3 72.4
Originality.ai Undetectable.ai by 4.9
86.8 91.7
Copyleaks Undetectable.ai by 20.9
53.5 74.3
Winston AI Undetectable.ai by 8.8
70.2 78.9
ZeroGPT Undetectable.ai by 6.4
74.0 80.4

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. How category scores work →

Academic Essay Application Essay Blog Post Business Email Marketing Copy Discussion Board News Article Academic Essay: Humanize AI Pro 82.5 · Undetectable.ai 86.0 Application Essay: Humanize AI Pro 60.4 · Undetectable.ai 73.8 Blog Post: Humanize AI Pro 76.0 · Undetectable.ai 57.5 Business Email: Humanize AI Pro 37.2 · Undetectable.ai 51.0 Marketing Copy: Humanize AI Pro 76.7 · Undetectable.ai 78.4 Discussion Board: Humanize AI Pro 81.2 · Undetectable.ai 78.9 News Article: Humanize AI Pro 66.8 · Undetectable.ai 51.8
Humanize AI Pro Undetectable.ai Outer ring = 100
Academic Essay 6 prompts Undetectable.ai by 3.5
82.5 86.0
Application Essay 6 prompts Undetectable.ai by 13.3
60.4 73.8
Blog Post 6 prompts Humanize AI Pro by 18.5
76.0 57.5
Business Email 3 prompts Undetectable.ai by 13.8
37.2 51.0
Marketing Copy 6 prompts Undetectable.ai by 1.7
76.7 78.4
Discussion Board 3 prompts Humanize AI Pro by 2.3
81.2 78.9
News Article 3 prompts Humanize AI Pro by 15.1
66.8 51.8

Head-to-head history

Overall score in every cycle both tools were tested. Undetectable.ai has finished ahead in 3 of 4 shared cycles.

50 60 70 80 90 June 2026 July 2026 August 2026 September 2026 June 2026: Undetectable.ai 80.09 (#5) June 2026: Humanize AI Pro 68.05 (#9) July 2026: Undetectable.ai 72.17 (#2) July 2026: Humanize AI Pro 70.49 (#3) August 2026: Undetectable.ai 61.49 (#8) August 2026: Humanize AI Pro 71.40 (#2) September 2026: Undetectable.ai 71.75 (#6) September 2026: Humanize AI Pro 70.07 (#7) 70.1 71.8
Humanize AI Pro Undetectable.ai
Cycle Humanize AI Pro Undetectable.ai Margin
September 2026 70.07 #7 71.75 #6 → 1.7
August 2026 71.40 #2 61.49 #8 ← 9.9
July 2026 70.49 #3 72.17 #2 → 1.7
June 2026 68.05 #9 80.09 #5 → 12.0

Where each one wins

Every measure above that one tool won outright, largest margin first within each group.

Humanize AI Pro

5 wins
  • Penalties Score None vs −6.0
  • Readability Score 61.8 vs 61.7
  • Blog Post Category 76.0 vs 57.5
  • News Article Category 66.8 vs 51.8
  • Discussion Board Category 81.2 vs 78.9

Undetectable.ai

12 wins
  • Bypass rate Score 82.1 vs 70.8
  • Meaning preservation Score 82.1 vs 74.7
  • Consistency Score 71.1 vs 65.3
  • Copyleaks Detector 74.3 vs 53.5
  • GPTZero Detector 72.4 vs 58.3
  • Winston AI Detector 78.9 vs 70.2
  • ZeroGPT Detector 80.4 vs 74.0
  • Originality.ai Detector 91.7 vs 86.8
  • Business Email Category 51.0 vs 37.2
  • Application Essay Category 73.8 vs 60.4
  • and 2 more

Questions people ask

Is Humanize AI Pro better than Undetectable.ai?

Undetectable.ai finished 1.7 points ahead of Humanize AI Pro in the September 2026 cycle, 71.75 to 70.07, ranking #6 against #7 in a field of 14. Undetectable.ai scored higher on 5 of 5 detectors and 4 of 7 writing categories. Both tools ran the same 33 prompts, scored by the same 5 detectors, under methodology v1.2.0; every input, output and verdict is published.

Which bypasses AI detectors better, Humanize AI Pro or Undetectable.ai?

Undetectable.ai posted the higher bypass rate, 82.1 vs 70.8, and scored higher on 5 of 5 detectors. Undetectable.ai led on GPTZero, Originality.ai, Copyleaks, Winston AI and ZeroGPT. The overall bypass gap is inside both 95% confidence intervals, so it is not a reliable difference.

Do Humanize AI Pro and Undetectable.ai keep the original meaning?

Undetectable.ai preserved meaning better, 82.1 vs 74.7 on our 0–100 similarity scale. On readability, Humanize AI Pro rated higher, 61.8 vs 61.7. Penalties this cycle: Humanize AI Pro None, Undetectable.ai −6.0.