The Best AI Humanizers Updated
The benchmark for AI humanizers.
HumanizerBench tests leading AI humanizers against GPTZero, ZeroGPT, Copyleaks, Winston AI, and Originality.ai. We publish every prompt, raw output, detector verdict, and scoring script so the rankings can be reproduced. We pay full price for every tool, use no affiliate links, and accept no payment for placement, removal, or higher scores. The benchmark is run transparently by WriteHuman, which is tested under the same methodology as every other tool.
This Cycle's AI Humanizer Benchmark
13 humanizers · 33 samples per humanizer · 5 detectors
| Rank Position in this cycle by overall score. Learn more → | Humanizer | Overall Weighted blend of bypass rate (42%), meaning preservation (32%), readability (16%), and consistency (10%). Penalties may reduce this score. Learn more → ↓ | Bypass Rate Fraction of detector tests where the humanized output was classified as human, across all 5 detectors. Learn more → | Meaning Semantic similarity (embedding cosine) between input and humanized output. Higher = output preserves the input's meaning. Learn more → | Readability Writing quality of the output — clarity, fluency, and naturalness, rated by a language model. Higher = better. Learn more → | Penalties Total points deducted from the overall score when output-quality issues were detected. Hover a row's chip to see why. Learn more → | Trend Leaderboard position across recent cycles. The line rises when the tool moves up the ranking, independent of absolute score. Learn more → | Last Tested |
|---|---|---|---|---|---|---|---|---|
| 1
▲ 1 | 73.07 | 81.6 | 72.9 | 56.2 | −1.0Penalties applied
| | 1d ago | |
| 2
▲ 3 | 72.17 | 95.7 | 73.0 | 55.9 | −10.0Penalties applied
| | 1d ago | |
| 3
▲ 6 | 70.49 | 70.4 | 74.3 | 60.3 | None | | 1d ago | |
| 4
▼ 3 | 68.07 | 81.2 | 68.5 | 44.5 | −3.0×2Penalties applied
| | 1d ago | |
| 5
▼ 1 | 66.42 | 70.7 | 75.3 | 43.9 | −1.0Penalties applied
| | 1d ago | |
| 6
▼ 3 | 64.84 | 65.9 | 73.8 | 42.9 | None | | 1d ago | |
| 7
▲ 3 | 62.84 | 80.6 | 64.7 | 61.5 | −8.0×2Penalties applied
| | 1d ago | |
| 8
▼ 1 | 61.52 | 81.6 | 63.0 | 60.6 | −10.0×3Penalties applied
| | 1d ago | |
| 9
▼ 1 | 61.47 | 73.4 | 60.9 | 72.1 | −8.0×3Penalties applied
| | 1d ago | |
| 10
▼ 4 | 59.66 | 76.0 | 69.8 | 55.7 | −10.0×2Penalties applied
| | 1d ago | |
| 11
-
| 54.13 | 42.3 | 73.2 | 67.1 | −5.0×3Penalties applied
| | 1d ago | |
| 12
-
| 53.38 | 0.0 | 94.5 | 82.1 | None | | 1d ago | |
| 13
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| 44.04 | 0.0 | 69.1 | 74.5 | None | | 1d ago |
Showing scores in overall column.
How scores are computed
See the full methodology →Overall score formula
- Bypass 42% Share of detector tests where the output was classified as human.
- Meaning 32% How well the output preserves the original meaning.
- Readability 16% How clear, fluent, and natural the writing reads, rated by a language model.
- Consistency 10% How evenly the humanizer performs across writing categories.
Penalties (right) are deducted from the overall score. Final score is clamped at 0.
Possible penalties
| Code | Penalty | Max |
|---|---|---|
| Identical to input The tool returned the input mostly unchanged. No real humanization happened. | −2.0 | −10.0 |
| Refusal The tool refused to humanize the input, often due to a content-policy block. | −1.0 | −10.0 |
| Meaning drift The output's meaning drifted significantly from the original input. | −1.0 | −10.0 |
| Length inflation The output ran much longer than the input, a common trick that pads text to dilute the AI signal. | −1.0 | −10.0 |
| Length deflation The output came back much shorter than the input. The rewrite dropped content instead of paraphrasing it. | −1.0 | −10.0 |
Maximum possible total penalty: −50.0 (off 100).
Archives
How we score
Raw data
Why This AI Humanizer Benchmark Exists
The AI humanizer market is full of overpromising tools, paid placements, and fake reviews. HumanizerBench helps people compare AI humanizer tools using real detector data, not marketing claims.
We're WriteHuman, one of the products being tested. That's the obvious objection, so every input, output, AI detector response, and scoring script is public. Anyone can review the data and re-run the numbers.
Read the full storyHow We Benchmark AI Humanizers
AI humanizer tools rewrite machine-generated text so it's less likely to be flagged by AI-content detectors. Most use a language model with a paraphrasing prompt and post-processing to alter perplexity, burstiness, and other statistical patterns detectors look for, while trying to preserve the original meaning.
HumanizerBench runs a fixed prompt set through every humanizer in the list, then submits the rewritten output to 5 leading detectors. We measure how well each AI text humanizer can bypass AI detection, along with meaning preservation against the source, readability, and consistency across writing categories, then combine those into an overall score.
Every input, every humanized output, every detector response, and every scoring run is published in our public GitHub repository. Vendors and third parties can independently reproduce the rankings; see the fairness policy for disputes.
Pick the best AI humanizer for your use case
The overall ranking is balanced across categories. If you need to humanize AI text, convert AI to human text, compare free AI humanizer options, or check performance against a specific AI detector, the rankings below re-weight the same benchmark data for that goal.
Best Overall AI Humanizer
The balanced overall score across every category and detector — the full leaderboard ranking
Best AI Humanizer for Students
Weights academic_essay category 2x vs. the main overall score
Best AI Humanizer for Essays
Weights academic_essay + application_essay categories 2x vs. the main overall score
Best AI Humanizer for GPTZero
Sorted by GPTZero detector score only
Best AI Humanizer for Originality.ai
Sorted by Originality.ai detector score only
Best AI Humanizer for Turnitin
Sorted by Originality.ai detector score (Turnitin proxy)
Best AI Humanizer for SEO
Weights blog_post + marketing_copy categories 2x vs. the main overall score
Best AI Humanizer for Academic Writing
Weights academic_essay + application_essay categories 2x vs. the main overall score
Best AI Humanizer for Marketing
Weights marketing_copy + blog_post categories 2x vs. the main overall score
Best Free AI Humanizer
Filtered to free-tier humanizers, sorted by overall score
AI Detectors We Test Against
We test every humanizer against the AI detectors and AI checkers most likely to be used by educators, publishers, and platforms. Each detector page shows which tools performed best against that specific detector.
- GPTZero AI Detector
One of the earliest AI text detectors, widely used by educators to check whether student writing was generated with AI.
- Originality.ai Detector
A subscription AI checker used by publishers, SEO teams, and content teams to detect AI writing and plagiarism.
- Copyleaks AI Detector
An enterprise AI checker and plagiarism-detection platform used by universities, businesses, and content-moderation teams.
- Winston AI Detector
An AI detector and plagiarism checker used to review writing for AI-generated content, readability, and originality.
- ZeroGPT AI Detector
A free, browser-based AI detector popular for quick checks of suspected AI-generated content.
Frequently Asked Questions
Answers to common questions about how HumanizerBench works, how rankings are calculated, how often results are updated, and how we keep the benchmark transparent.
What is an AI humanizer?
An AI humanizer is a tool that rewrites machine-generated text to make it sound more natural and less likely to be flagged by AI-content detectors. People use these tools to humanize AI text, convert AI to human text, remove AI detection signals, or make AI text undetectable while preserving the original meaning.
How does this benchmark test AI humanizers?
Each cycle, every humanizer in the catalog processes the prompt set across multiple writing categories. The output is submitted to leading detectors. We record raw responses, measure how well each tool can bypass AI detection, score meaning preservation against the original text, and combine the results into an overall score. Every input, output, detector response, and scoring script is published in our public repository.
What does the overall score mean?
The overall score blends AI detector bypass rate (42%), meaning preservation (32%), readability (16%), and category consistency (10%). Higher is better. The full formula and scoring script are published on the methodology page and in the public repository.
How often is the leaderboard updated?
Monthly. Each cycle's results are archived under its own URL (for example /leaderboard/<cycle>) so historical best AI humanizer rankings remain accessible alongside the latest cycle.
Are these rankings paid placements?
No. We don't accept payment for placement, removal, or score adjustment. HumanizerBench is designed to avoid the paid placements, fake reviews, and marketing claims common in the AI humanizer market. The fairness policy spells out exactly what we will and won't do, and because the scoring script and raw data are public, any vendor or third party can independently reproduce the rankings.
WriteHuman operates this benchmark. How is bias handled?
WriteHuman is tested with the same prompt set, methodology, and scoring as every other humanizer. The scoring script is deterministic and open source. If a vendor disputes a result, the published raw data lets anyone re-run the calculation. The fairness policy covers disputes.
Which AI humanizer is best at bypassing GPTZero, Originality.ai, or other specific detectors?
Each detector has its own page (for example /detectors/gptzero) showing which humanizers are best at bypassing that specific AI detector. You can compare results for GPTZero, Originality.ai, ZeroGPT, Copyleaks, and Winston AI. A high single-detector score does not necessarily mean the tool is the best AI humanizer overall; see the main ranking for the balanced view.
Why do you publish all the raw test data?
Because the alternative is asking readers to trust us. Every input, every humanized output, every AI detector response, and every scoring run is published in the GitHub repository. That makes the benchmark reproducible instead of dependent on our reputation.