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

June 2026 prompt evidence

Each of these 30 prompts was written by a frontier model, then handed to all 13 ranked humanizers, and every rewrite was submitted to 5 commercial AI detectors. Every run was screen-recorded. Open a prompt to read the input, every tool's rewrite, each detector's verdict, and to watch the recording of that run.

30
Prompts
13
Tools ranked
390
Humanizer outputs
1950
Detector verdicts
How to read these scores

Each detector returns a human-likelihood on a common 0 to 1 scale, where 1 means it judged the text human-written and 0 means it flagged it as AI. On these pages a verdict counts as passed when that score is at least 0.50, the midpoint of the detector's own scale. That threshold exists only to draw the chips: the bypass rate on the leaderboard is the mean of each test's median score across the 5 detectors, a continuous number, so a tool's pass count and its bypass rate will not be the same figure.

Meaning is the input↔output embedding cosine and readability is a language-model writing-quality rating, both published per test in tests.json. Words is the output's length as a multiple of the input's; the scoring code penalizes ratios above 1.40 or below 0.60. Full definitions live in the methodology.

Prompt Category Written by Input words Passed Failed Open
01 Listicle Blog Blog Post claude-opus-4-7 386 7 12
02 Lit Review Academic Essay Gemini 3.5 Flash 390 9 9
03 Discussion Post Discussion Board claude-opus-4-7 261 9 7
04 Cover Letter Application Essay Gemini 3.5 Flash 367 0 13
05 Landing Copy Marketing Copy GPT-5.5 307 6 11
06 Product Desc Marketing Copy claude-opus-4-7 196 6 10
07 Argumentative Essay Academic Essay claude-opus-4-7 385 8 8
08 News Article News Article claude-opus-4-7 390 5 12
09 Product Desc Marketing Copy GPT-5.5 195 6 10
10 Landing Copy Marketing Copy Gemini 3.5 Flash 281 5 12
11 Discussion Post Discussion Board Gemini 3.5 Flash 242 10 7
12 Howto Blog Blog Post Gemini 3.5 Flash 386 3 11
13 Personal Statement Application Essay GPT-5.5 364 5 10
14 Cover Letter Application Essay claude-opus-4-7 397 2 13
15 Argumentative Essay Academic Essay GPT-5.5 435 8 7
16 Howto Blog Blog Post claude-opus-4-7 398 8 9
17 Personal Statement Application Essay Gemini 3.5 Flash 341 6 12
18 Lit Review Academic Essay claude-opus-4-7 390 7 10
19 Listicle Blog Blog Post Gemini 3.5 Flash 450 10 7
20 Listicle Blog Blog Post GPT-5.5 450 9 8
21 Product Desc Marketing Copy Gemini 3.5 Flash 173 7 11
22 News Article News Article GPT-5.5 460 10 10
23 Argumentative Essay Academic Essay Gemini 3.5 Flash 394 5 12
24 Personal Statement Application Essay claude-opus-4-7 359 8 11
25 Discussion Post Discussion Board GPT-5.5 257 6 8
26 Howto Blog Blog Post GPT-5.5 438 7 6
27 Cover Letter Application Essay GPT-5.5 388 4 11
28 Lit Review Academic Essay GPT-5.5 435 8 11
29 News Article News Article Gemini 3.5 Flash 396 5 10
30 Landing Copy Marketing Copy claude-opus-4-7 314 3 13

"Passed" counts the ranked tools whose rewrite of that prompt at least 4 of the 5 detectors scored as human-written (0.50 or above); "Failed" counts those flagged by at least one detector that scored them; "Hardest" is the single detector that flagged the most rewrites of that prompt.

Recordings

Every tool was run in a recorded sitting. Each recording opens here from the start; the outputs pages jump to the exact moment a prompt was run.

  • Stealth Writer 6:32 · 30 prompts · Jun 2, 2026
  • WriteHuman 7:25 · 30 prompts · Jun 1, 2026
  • HIX Bypass 11:26 · 30 prompts · Jun 2, 2026
  • Humbot 14:51 · 30 prompts · Jun 2, 2026
  • Undetectable.ai 8:49 · 30 prompts · Jun 1, 2026
  • AI Humanize io 12:24 · 30 prompts · Jun 2, 2026
  • StealthGPT 12:59 · 30 prompts · Jun 1, 2026
  • Phrasly 13:22 · 30 prompts · Jun 2, 2026
  • Humanize AI Pro 8:49 · 30 prompts · Jun 2, 2026
  • Walter Writes 16:17 · 30 prompts · Jun 2, 2026
  • Super Humanizer 5:13 · 30 prompts · Jun 2, 2026
  • Grammarly 9:37 · 30 prompts · Jun 2, 2026
  • NoteGPT 12:41 · 30 prompts · Jun 2, 2026
  • BypassGPT not ranked this cycle 16:46 · 30 prompts · Jun 2, 2026

Session recording