Best AI Humanizer for GPTZero

GPTZero catch rate

Caught means GPTZero gave a human-likelihood score below 0.50 on a 0 to 1 scale. Avg human score is the mean score on a 0 to 100 scale. Rank 1 caught the most that month.

Humanizers that pass GPTZero

Every AI humanizer we tested against GPTZero in October 2026, ordered by its average GPTZero score. 6 of 14 passed GPTZero on at least 80% of their outputs. The top three passed 30, 30 and 29 of their 30 outputs, and first place changed hands in 3 of the last 4 monthly updates.

GPTZero humanizer results, October 2026

Rank Position by average GPTZero score this cycle. Learn more →	Humanizer	ScoreGPTZero score Average of GPTZero's human-likelihood scores on this tool's outputs, where 100 means every output was scored as human. The table is ordered by this column. Learn more → ↓	Passed Outputs GPTZero scored as human (a human-likelihood of 0.50 or higher), out of the tool's outputs it scored. Ranked by share passed. Click a count to read this tool's outputs. Learn more →	Sep 2026September 2026 This tool's GPTZero score in September 2026. "New" means it was not tested that month. Learn more →	Overall Overall score across all detectors, after penalties. Learn more →
1	WriteHuman writehuman.ai	99.5	30/30	71.8	74.89
2	Phrasly phrasly.ai	98.6	30/30	81.4	61.79
3	StealthGPT stealthgpt.ai	94.8	29/30	77.4	74.50
4	Clever AI Humanizer cleverhumanizer.ai	91.4	28/30	new	69.02
5	Walter Writes walterwrites.ai	87.8	28/30	78.3	63.53
6	Undetectable.ai undetectable.ai	85.0	27/30	72.4	71.18
7	AI Humanize io aihumanize.io	70.0	22/30	55.8	68.24
8	Humbot humbot.ai	65.6	21/30	new	61.74
9	Humanize AI Pro humanizeai.pro	54.6	18/30	58.3	68.87
10	Super Humanizer superhumanizer.ai	46.6	15/30	54.6	67.58
11	Stealth Writer stealthwriter.ai	40.9	13/30	33.9	65.98
12	HIX Bypass bypass.hix.ai	11.4	4/30	28.1	65.14
13	SupWriter supwriter.com	8.9	3/30	21.0	62.75
14	Grammarly grammarly.com	3.0	1/30	15.9	61.29

Swipe the table sideways to see every column.

Gold, silver and bronze mark the top three in this month's columns, ties sharing a color; Passed is ranked by share of outputs passed.

GPTZero compared with ZeroGPT and the other detectors

In October 2026, GPTZero caught 36.0% of humanized outputs and ZeroGPT caught 14.8%. On the 420 outputs both scored this month, they gave the same verdict on 65.5%. GPTZero gave the same verdict as Originality.ai most often (70.7% of outputs) and as Pangram least often (52.6%).

The six detectors on the same humanized outputs, October 2026

Detector	Caught	Rate Catch rate	Avg score Avg human score	vs Sep 2026 Change since Sep 2026	Only it Only it caught	Agrees Same verdict as GPTZero
Pangram	348 of 420	82.9%	16.9	n/a	147	52.6%
GPTZero	151 of 420	36.0%	61.3	−11.2	1
ZeroGPT	62 of 420	14.8%	76.5	−3.9	0	65.5%
Copyleaks	58 of 420	13.8%	85.9	−19.1	0	66.9%
Originality.ai	48 of 420	11.4%	87.2	−12.1	1	70.7%
Winston AI	30 of 420	7.1%	91.8	−28.3	1	65.5%

Swipe the table sideways to see every column.

Change is in points of catch rate. Only it caught counts outputs no other detector caught, of the 420 all six scored.

What GPTZero catches

By writing type, GPTZero caught humanized application essays and discussion board posts most often (50% each) and blog posts least often (20%, 17 of 84). Blog posts have been its least-caught type in all five months.

The second row pools the other detectors' verdicts on the same outputs. Each type had 3 to 6 prompts this month.

Tools that pass the other detectors but not GPTZero

These humanizers passed the other five detectors at least 30 points more often than GPTZero in October 2026, counting tools with 20 or more outputs GPTZero scored.

Humanizers with a much lower pass rate on GPTZero than on the other detectors, October 2026

Humanizer	GPTZero Passed GPTZero	Others Passed the others	Gap	Months Months with the gap
HIX Bypass	13% 4/30	70% 105/150	−57 pts	5 of 5
SupWriter	10% 3/30	62% 93/150	−52 pts	2 of 2
Grammarly	3% 1/30	45% 67/150	−41 pts	1 of 5
Stealth Writer	43% 13/30	79% 119/150	−36 pts	5 of 5

Swipe the table sideways to see every column.

Outputs only GPTZero caught

In October 2026, GPTZero caught 1 humanized output that all five other detectors passed. That is 1% of the 69 outputs the others all let through. The example below has the widest gap between GPTZero and the others, one per tool and prompt.

Raw scores run from 0 to 1, as on the evidence pages the prompt links open.

Of the 30 prompts, GPTZero caught the largest share of tools on two prompts, including Product Desc · gemini-3-8-flash (10 of 14) and the smallest share on two prompts, including Argumentative Essay · claude-sonnet-5-5 (1 of 14). All 30 October 2026 prompts

Choosing a humanizer for GPTZero

The humanizer ranking above sorts by average GPTZero score alone. It leaves out the other detectors, and it leaves out meaning and readability. That makes it a narrow view. A tool can do well against GPTZero while changing what your text says or reading awkwardly, so check the Overall column in the ranking, and the Meaning and Readability columns on the leaderboard, before you choose. If a tool ranks high here but low on the leaderboard, find out what it gave up before you rely on it. The leaderboard balances every detector we test with meaning and readability.

Detectors change over time, and a result from one cycle may not hold in the next. HumanizerBench runs a new test cycle each month, so note which cycle you are reading and look at each tool's history on its results page.

When you try a tool, use a paragraph of your own writing, check the result in GPTZero yourself, then read the output line by line for changed facts and lost citations.

Questions about GPTZero