StealthGPT and Rephrasy are AI humanizer tools. You paste in AI-generated text (from ChatGPT, Claude, Gemini and so on) and each tool rewrites it to read more like human writing, with a built-in AI detector to check the score. Both market themselves heavily on bypassing detectors such as Turnitin, GPTZero and Originality.ai. I compared them from their own pricing and product pages on 27 October 2026. I have not run either tool against any detector, so every bypass claim below is the vendor’s own.
A word of caution about AI detection bypass claims
Two things are worth saying plainly. First, AI detectors and humanizers are in a constant back and forth, so a tool that passes a detector this month may not next month, whatever the marketing says. Second, if you’re a student, submitting AI-generated text as your own work breaks most universities’ academic integrity rules whether or not a detector catches it. These tools are more defensible for tidying up your own drafts, marketing copy or SEO content where AI use is allowed.
StealthGPT features
- AI humanizer and AI detector on every plan, with a history of past jobs.
- In-text citations and Stealth Insights.
- Support for 100+ languages.
- File upload: .doc and .txt on Pro, plus PDF and images on Max and Enterprise.
- An iOS app, a Chrome extension and MCP access so you can use it inside Claude, Cursor and similar tools.
- Team seats on Max (3) and Enterprise (5), and an API on Enterprise.
- An optional add-on called Samurai.
StealthGPT’s pricing page leads with a claim that its new model beats Pangram and other major AI detectors. It also says it has more than 1.5 million active users. Those are vendor claims.
Rephrasy features
- AI humanizer with several humanizer models (the homepage mentions Superstealth and v4) and a writing style feature that clones your own style.
- A free AI detector built into the homepage tool.
- A free re-humanize option if the first output doesn’t pass.
- Support for 50+ languages.
- A Chrome extension that works in Google Docs, Gmail and LinkedIn.
- A Humanizer API on Business and Professional, and an AI Detector API on Professional.
- Plagiarism checker credits on some plans.
Rephrasy says it guarantees 100% pass rates on all major AI detectors and that it has more than 200,000 users. Again, those are its own claims, and a guarantee is only as good as the refund terms behind it.
Pricing and word limits
| Plan | StealthGPT | Rephrasy |
|---|---|---|
| Short term | None | Quick Pass $14.99 one-time: 24 hours of unlimited humanizing and detection |
| Entry | Pro $29.99/month: 50,000 words, 1,000 words per request | Growth $99/year ($8.25 a month): 100 humanizations a month up to 2,000 words each |
| Middle | Max $49.99/month: 200,000 words, 2,000 per request, 3 seats | Business $120/year ($10 a month): 200 humanizations, API, 3 writing styles |
| Top | Enterprise $179.99/month: 1,000,000+ words, API, custom models | Professional $220/year ($18.33 a month): 400 humanizations, detector API |
| Lifetime | None | Lifetime Access $199: unlimited humanizer and detector, 2,400 credits |
StealthGPT says yearly billing saves up to 17.5%. Rephrasy’s page showed yearly prices by default (saving up to 60% against monthly), so the monthly figures above are the yearly price divided by twelve.
On the published numbers, Rephrasy is far cheaper. Its Growth plan covers up to 200,000 words a month for $99 a year, while StealthGPT’s 200,000 word Max plan is $49.99 a month. The lifetime deal is also unusual in this category. The usual caution applies to any lifetime deal: it depends on the company staying in business and keeping the product working.
Writing quality and how the text is rewritten
Neither vendor explains its method in much detail. Rephrasy says its humanizer looks for the patterns that give AI text away (predictable phrasing, uniform rhythm, stock transitions) and rewrites with varied sentence lengths and a more natural flow while keeping facts and meaning intact. StealthGPT says less about method and more about results.
The risk with any rewrite tool is that it changes meaning or adds errors. For an essay, report or article, read every sentence of the output against your original. If a section gets flagged by a detector after humanizing, rewriting it yourself is usually more reliable than running it through the tool again.
Ease of use for writing and humanize jobs
Both work the same basic way: paste text, choose a mode, humanize, then check the AI score with the built-in detector. StealthGPT adds more ways in (iOS app, Chrome extension, MCP), and Rephrasy adds custom writing styles and a Chrome extension that works inside Google Docs and Gmail.
How they compare with Undetectable AI, StealthWriter and Originality
Undetectable AI sells word-based plans from $9.99 a month (10,000 words) and offers a refund of the humanization cost if output is flagged as not human, according to its pricing page. StealthWriter has a free plan with 10 humanizations a day and paid plans from $20 a month. Both are worth comparing on price with the two tools here.
On the detection side, Originality.ai is one of the detectors these humanizers say they can beat, and it is also the detector many publishers use to check content. If your work will be checked by a specific detector, that is the one to run your own text through.
Limits and drawbacks
- StealthGPT has no free plan on its pricing page, and its 1,000 word per request limit on Pro means splitting longer essays.
- StealthGPT’s API is only on the $179.99 Enterprise plan.
- Rephrasy’s monthly prices are not shown by default, and its lifetime deal is presented as a limited time offer.
- Both make strong detector bypass claims that I could not check, and detectors change often.
Which AI text humanizer should you pick?
For most individual users, Rephrasy looks like better value on paper, especially the yearly Growth plan or the 24 hour pass if you only need it once. I would pick StealthGPT if you need a big monthly word allowance, team seats, citations or MCP access inside your AI tools. Whichever you choose, read the output yourself before using it. A humanized text that passes a detector but reads badly or changes your meaning is not much use.
Alternative AI writer and detector tools
- Undetectable AI: a humanizer and detector with word-based monthly plans.
- WriteHuman: a humanizer priced per request with a small free allowance.
- StealthWriter: a humanizer with a free daily allowance.
