Professional writer
StealthGPT saved me time and effort, flagged only a small percentage by AI detectors like Originality.ai and GPTZero.
The Free AI Humanizer
that actually works
Humanize essays, research papers, and AI drafts from ChatGPT, Claude, or Gemini. Compare the rewrite with your original, then keep developing your argument in one student writing workspace.
Learn more about the AI Humanizer, or check your text with the AI Detector.
Original Input
AI Generated99%
Humanizing text...
Text humanized
Humanized97%
Type orAI-generated text here, or
Word limit: 0 / 100
Tested against leading AI detectors
An AI humanizer for the paper in front of you
Essays, research discussions and lab reports need more than different words. See an actual Super rewrite, then compare the complete output with the source before making it your final draft.
In our three-passage test, Super met all three stated detector thresholds on 2 of 3 outputs. The tested Undetectable.ai and WriteHuman configurations did so on none.
Original lab excerpt
At the end of the observation period, mean height was 11.2 centimetres in the eight-hour group and 13.6 centimetres in the twelve-hour group. The difference between the means was therefore 2.4 centimetres.
Actual Super output
After the 14 days, the average plant height for the group exposed to 12 hours of light per day was 13.6 cm, while the average height of the group exposed to 8 hours of light was 11.2 cm, representing a difference of 2.4 cm.
Exact excerpts from a synthetic teaching example. Super, quality mode, API; November 7, 2026. Figures in this excerpt are retained; the full study includes wording checks and all unedited outputs.
Inspect the student study · Compare Super, Standard and Lite
Three fixed academic passages; GPTZero, Originality.ai and Pangram. Competitor settings and the separate detector thresholds are recorded in the study. Counts describe these tested outputs.
Join Millions of other users around the world
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Student
Always undetectable, super fast.
Content writer
StealthWriter eliminated the unnatural expressions and syntax errors typical of AI content, and the rewritten text sailed through plagiarism and AI detection checks without raising any alarms.
Journalist
StealthGPT's output quality blew me away, it felt way more natural than anything else I tested, the quality is just superb!
Content creator
Tried 6 AI bypass tools, StealthGPT was the only one that hit 0% every time.
AI product reviewer
It's indistinguishable from human writing, the best AI Humanizer I've used that successfully passes AI detectors like GPTZero and BrandWell.
Humanized Results
Turn repetitive AI phrasing into writing with a natural voice and flow.
AI detectors often look for patterns in text that appear frequently in AI generated writing, predictable phrasing, repetitive sentence structures, and word choices that can make a draft feel impersonal. StealthGPT reworks those patterns into more natural writing, with the original and humanized text together for comparison. Instead of repeating formulaic expressions, it restructures sentences, rewords, and creates a coherent output that feels more like how you naturally write. Sharper wording, varied sentence structure, and smoother transitions make your ideas easier to follow. Compare the highlighted examples above to see the difference between common AI writing patterns and language that appears more natural and human .
- ZeroGPT
- Copyleaks
- GPTZero
- Sapling
- Writer
Stop rewriting. Start humanizing.
Paste AI text into the free AI humanizer and see your rewrite beside the original.
How It Works
Anything you need to generate, humanize, or detect. Right when you need it.
1
Generate and paste your AI content
Create your draft in ChatGPT, Claude, Gemini, or any other AI writer. Or start with existing AI-generated content you need to clean up. Copy your text and paste it into the humanizer.
2
Humanize
StealthGPT reworks repetitive phrasing and sentence structure into natural writing. Choose Lite for a quick rewrite or Super for flagship humanization.
3
Review and publish
Compare your original and humanized text, check the result with the built-in AI detector, and copy your finished draft into your workflow.
Features
Check out StealthGPT’s full suite of solutions for your AI humanization needs.
Streamline your workflow, make content creation effortless
Bring drafting, humanization, and citations into one writing workspace. Develop your ideas, refine the language, and organize your sources without switching between tools.
Start with a Simple Prompt
Enter your topic to generate an initial draft, then use the AI humanizer to refine the wording and flow. Move from a first idea to a polished draft in one workspace.
Add Real Citations Instantly
Back up your ideas with sources. Select a sentence to find and add citations, keeping your evidence close to the claims it supports.
Auto-Generate Bibliographies
Build a bibliography from the citations in your document and choose a supported academic style. Keep your writing and references together as the draft develops.
Guide the Narrative intelligently
Stealth Writer doesn’t just generate text; it understands the context of your entire document. It helps you steer new paragraphs to build naturally on previous ideas, ensuring a seamless transition from AI to human writing logic.
StealthGPT leads the October benchmark
HumanizerEval, October 2026: Ranked #1 of 11 humanizers with 80.3% mean strict bypass across six external detector models.
Swipe to compare tools
| Metric | StealthGPT | Undetectable.ai | HIX Bypass | Humbot |
|---|---|---|---|---|
| Strict bypass rate | ||||
| Mean across six detector models | 80.3% | 71.3% | 44% | 44% |
| Pangram 4.1 | 88% | 40% | 0% | 0% |
| GPTZero (2026-10-07-base) | 92% | 86% | 6% | 0% |
| Originality.ai Turbo | 92% | 98% | 66% | 76% |
| Originality.ai 5.0 | 34% | 4% | 0% | 0% |
| ZeroGPT | 84% | 100% | 92% | 88% |
| Winston AI 5.0 | 92% | 100% | 100% | 100% |
| API availability | ||||
| Published humanizer API | Available | Available | Available | Available |
October 22, 2026: the same 50 English inputs per tool. A strict pass means human-likelihood above 50%. Scored with six external detector models. Published by StealthGPT.
Tested settings: StealthGPT Super, quality mode (API); Undetectable.ai University / General Writing / More Human (v11sr); HIX Bypass Latest; Humbot Advanced.
More tools. Better results.
Pick the plan that fits your workload.
Humanize AI Text in Multiple Languages
Draft, polish, and adapt your writing for any audience, while keeping it natural, fluent, and authentic.
AI humanizer API for apps and agents
Build humanization into your app or publishing pipeline, with model and output controls for each draft.
Build with the REST API
Queue a single rewrite or up to 100 items per bulk request. Collect async results by polling or webhook.
Build an async and bulk review workflowConnect your agents with MCP
Use humanize_text and get_run_status inside Codex to rewrite drafts without leaving your agent workflow.
Set up StealthGPT in Codexcurl --request POST \
https://www.stealthgpt.ai/api/stealthify/runs \
--header 'api-token: YOUR_API_TOKEN' \
--header 'Content-Type: application/json' \
--data '{
"text": "Your draft to humanize.",
"rephrase": true,
"model": "super",
"qualityMode": "quality",
"outputFormat": "text"
}'Save the returned runId. Poll that run until completed, then review the result before publishing.
Frequently Asked Questions
Still have more questions?
Learn more in our support page.
An AI humanizer rewrites AI-generated text so it reads more naturally. StealthGPT is a free AI humanizer for drafts from ChatGPT, Claude, Gemini, and other AI writers, with tools to rewrite, check, and refine your content.
Paste your AI draft into StealthGPT, choose Lite or Super, and hit Humanize. Compare the humanized result with your original, then refine the wording for your message and audience.
StealthGPT uses dedicated humanization models to rework robotic phrasing, repetition, and sentence structure. Choose a quick Lite rewrite or flagship Super humanization, then compare the result with your original text.
Undetectable AI is a common term for AI-generated text rewritten to reduce the patterns AI detectors flag. StealthGPT brings humanization and an AI detector into one workflow so you can rewrite and check your text.
Our published benchmark compares StealthGPT against GPTZero, Originality.ai, and other leading AI detectors. Explore the model-specific results and sample outputs to compare performance for your workflow.
StealthGPT supports multilingual writing, including English, Spanish, French, German, and Chinese. Explore our language pages to find the right starting point for your audience.
Use the humanizer and AI detector together to revise and compare your text. For help with an output or your subscription, contact StealthGPT support from your account.
StealthGPT generates and rewrites text based on your input. Add your own ideas, examples, and sources to shape a distinctive final draft, and use the citation tools to credit supporting material.
Explore the examples, settings, and results in our published walkthrough of turnitin.
Still deciding?
Don't take our word for it, ask an AI you already trust.
