AI Humanizer Benchmark

November 2026 prompt evidence

This cycle used 33 prompts, each with its own AI-written input text. All 10 ranked humanizers rewrote every input text, and 7 commercial AI detectors scored each rewrite. Pick a row below to see a prompt's input text, each tool's rewrite, and every detector's score.

Cycle
33
Prompts
10
Tools ranked
330
Humanizer outputs
2310
Detector verdicts
PromptCategoryInput modelInput wordsPassedFailedHardest
01Argumentative essayAcademic essayGPT-5.6 Terra315010Originality.ai
02Lit reviewAcademic essayClaude Sonnet 5296210Originality.ai
03Cover letterApplication essayGemini 3.5 Flash291010Originality.ai
04Personal statementApplication essayGPT-5.6 Luna27119Originality.ai
05How-to blogBlog postClaude Haiku 4.5280110Originality.ai
06Listicle blogBlog postGemini 2.5 Flash329010Originality.ai
07Business emailBusiness emailGPT-5.6 Terra262010Originality.ai
08Landing copyMarketing copyClaude Sonnet 5299110Pangram
09Product descriptionMarketing copyGemini 3.5 Flash19159Originality.ai
10Discussion postDiscussion boardGPT-5.6 Luna26819Originality.ai
11News articleNews articleClaude Haiku 4.5300010Originality.ai
12Argumentative essayAcademic essayGemini 2.5 Flash259210Originality.ai
13Lit reviewAcademic essayGPT-5.6 Terra349110Pangram
14Cover letterApplication essayClaude Sonnet 5314010Originality.ai
15Personal statementApplication essayGemini 3.5 Flash292010Originality.ai
16How-to blogBlog postGPT-5.6 Luna313010Originality.ai
17Listicle blogBlog postClaude Haiku 4.5281010Originality.ai
18Business emailBusiness emailGemini 2.5 Flash188110Pangram
19Landing copyMarketing copyGPT-5.6 Terra257110Originality.ai
20Product descriptionMarketing copyClaude Sonnet 519129Originality.ai
21Discussion postDiscussion boardGemini 3.5 Flash251010Originality.ai
22News articleNews articleGPT-5.6 Luna298010Originality.ai
23Argumentative essayAcademic essayClaude Haiku 4.5312210Originality.ai
24Lit reviewAcademic essayGemini 2.5 Flash258010Originality.ai
25Cover letterApplication essayGPT-5.6 Terra300010Originality.ai
26Personal statementApplication essayClaude Sonnet 5329010Originality.ai
27How-to blogBlog postGemini 3.5 Flash298110Originality.ai
28Listicle blogBlog postGPT-5.6 Luna323010Pangram
29Business emailBusiness emailClaude Haiku 4.5228010Originality.ai
30Landing copyMarketing copyGemini 2.5 Flash277010Originality.ai
31Product descriptionMarketing copyGPT-5.6 Terra195010Originality.ai
32Discussion postDiscussion boardClaude Sonnet 5252010Originality.ai
33News articleNews articleGemini 3.5 Flash295110Pangram

How to read the columns. A tool counts as “Passed” when 6 or more of the 7 detectors gave its rewrite a human-likelihood score of 0.50 or higher. It counts as “Failed” when any detector that returned a score put it below 0.50. So one tool can count in both columns. “Hardest” is the detector that caught the most tools on that prompt. If several are tied, only one is shown.

How to read these scores

Each detector's result is converted to a human-likelihood score between 0 and 1. A score of 0 means the detector is sure the text is AI. A score of 1 means it is sure the text is human. Dots are green at 0.50 or above and red below. Hover a dot to see its exact score. The 0.50 cut-off only sets the dot colors. A tool's bypass rate on the leaderboard takes the median of the 7 detector scores for each test, then averages those medians. That gives a continuous number, so it will not match the share of green dots. The same goes for each per-detector rate. It is the average of that detector's scores (the number detector pages rank by), not a count of green dots.

Raw data

Each ranked tool has its own JSONL file for this cycle, with one row per prompt. A row holds the prompt, its input text, the tool's rewrite, its meaning preservation and readability scores, and the run status. Scores from the 7 detectors are in separate files, one per detector, in the cycle's GitHub folder.

CleverHumanizer
33 rows · .jsonl
UndetectedGPT
33 rows · .jsonl
Rephrasy
33 rows · .jsonl
GPTinf
33 rows · .jsonl
SuperHumanizer
33 rows · .jsonl
SmartHumanizer
33 rows · .jsonl
HIX Bypass
33 rows · .jsonl
StealthGPT
33 rows · .jsonl
ReHumanize
33 rows · .jsonl
Undetectable AI
33 rows · .jsonl