StealthWriter is a web-based AI text humanizer paired with its own AI detector, letting writers rewrite AI-assisted drafts sentence by sentence and scan the result before and after. Built by AiVantage LLC for writers, marketers and researchers who want AI-assisted prose to read naturally.
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StealthWriter is a browser-based writing tool that does two related things: it rewrites text so that it reads more like natural human prose, and it scans text to estimate how likely a detector is to flag it as machine-written. The two halves are meant to be used together — you scan a draft, rewrite it, then scan the result again to see what changed.
The product describes its own core action plainly: StealthWriter rewrites AI-generated content so it reads naturally human, polished, and ready to use. In practice this means you paste a draft that came out of a general-purpose model such as ChatGPT, Claude, or Gemini, choose how aggressively you want it reworked, and get back a version with different phrasing, rhythm, and sentence construction.
It is worth being precise about what kind of product this is, because the category has a naming problem. Tools in this space are marketed under at least three different labels — humanizers, bypassers, and paraphrasers — and the label chosen usually says more about who is doing the marketing than about what the software does. StealthWriter's own legal terms use the most conservative of the three: the Terms and Conditions describe it as a state-of-the-art paraphrasing and content rewriting tool powered by artificial intelligence, designed to help users create unique, high-quality content efficiently.
The service is run by AiVantage LLC, a company registered in Wyoming, and the About page names an individual owner rather than hiding behind a brand: StealthWriter is a service of AiVantage LLC. Owner: Maher Mansour. The same page publishes a legal name, a contact email, a telephone number, and a physical mailing address in Sheridan, Wyoming.
This matters more than it might seem. A large share of products in the AI-humanizer category operate anonymously, with no named legal entity, no address, and no way to identify who is responsible if billing goes wrong or data is mishandled. StealthWriter publishes all three. That does not make its product claims true, but it does mean there is an accountable party behind the service — a basic threshold that a surprising number of competitors do not clear.
If you have encountered StealthWriter before, you may remember it differently. Older directory listings and third-party pages still describe it primarily as a way to bypass Turnitin, GPTZero, and Originality AI, and promise a 100% human score. The current site does not talk that way. The homepage, the About page, and the FAQ now consistently use the language of humanizing, clarity, and natural expression rather than evasion, and the Terms go further still — they explicitly disclaim the use case that the old marketing implied.
Readers should treat the older framing as outdated. This page describes the product as it currently presents itself, and separately examines whether either version of the claim holds up.
The rewriting engine works on one sentence at a time and exposes a strength control. The product describes it as follows: Rewrites AI text with natural human phrasing. Choose light, medium, or aggressive rewrite levels. Lighter settings preserve more of your original wording and are appropriate when a draft is mostly fine and you want to smooth a few passages; aggressive settings restructure more heavily and diverge further from what you wrote.
An independent test of the tool identified a structural property of this engine that is useful to know before you rely on it: This shows us that StealthWriter performs sentence level rewriting only. In other words, it doesn't add or remove any sentences. That is a real constraint with real consequences, and it cuts both ways. Because sentence count and order are preserved, the output stays aligned with your original structure and is easy to review side by side. But because the engine never merges, splits, reorders, or deletes anything, it cannot fix problems that live above the sentence — a paragraph that argues in circles, a section in the wrong order, a conclusion that does not follow from the evidence. Those are exactly the weaknesses that long AI-generated drafts tend to have, and no amount of rewriting at the sentence level will repair them.
Rather than sending you elsewhere to check results, the product includes its own scanner and positions it as a verification step around the rewrite. The scanner reports at the level of individual sentences: Sentence-by-sentence analysis with color-coded highlights showing exactly what's flagged. In practice you get a paragraph-level view of which specific sentences are driving a score, which is considerably more actionable than a single percentage for the whole document.
The detector can also be tried without committing to anything. The homepage embeds a live scanner with an explicit invitation: Paste any text below to instantly check how likely it is to be flagged as AI-generated. No account needed. For evaluating whether the product is worth an account at all, this is the fastest possible test — you can compare its verdicts against detectors you already trust before you sign up.
There is an important caveat about what this detector can and cannot tell you, which the Limitations section below addresses in detail. In short: a favourable score from a tool that is also selling you the rewriting is not independent evidence, and no detector's score — this one included — establishes how a different detector will rule.
Instead of accepting whatever the model produces, you can intervene per sentence: Click any sentence to choose from multiple alternatives. Fine-tune the output to your voice. This is the feature that most distinguishes careful use from careless use of the tool. Machine rewriting frequently produces sentences that are grammatical but slightly wrong — a shifted emphasis, an idiom that does not fit the register, a technical term swapped for a near-synonym that means something else. Being able to reject a candidate and pick another, sentence by sentence, is what makes it possible to keep the meaning you intended.
The rewriting engine is versioned, and older versions remain selectable. According to the product's changelog, The humanizer model selector now includes the Ghost 5.2 generation while keeping previous-generation Ghost 5.1 and Ghost 4.6 options available under Legacy. Ghost 5.2 Mini is described as the default lightweight option built for fast rewrites, while Ghost 5.2 Pro is tuned for more coherent structure, smoother flow, and better readability than the Mini model.
Keeping legacy generations available is a practical decision that acknowledges something the marketing does not: output characteristics change between versions, and a newer model is not automatically better for every text. Users who have tuned a workflow around a particular generation's voice can stay on it.
Non-English text is handled natively rather than through a translate-rewrite-translate detour. The changelog states that The 5.1 humanizer now supports major world languages — including German, Spanish, Portuguese, French, Italian, Dutch, Chinese, Japanese, and more. Whether output quality in these languages matches English is not something the vendor documents, and no independent test of its non-English output surfaced during this research, so treat multilingual support as available but unquantified.
One changelog entry describes a capability that deserves to be stated plainly rather than buried: StealthWriter can now remove the Claude watermark from AI-generated text. Humanized output no longer carries Anthropic's invisible AI watermark.
This is a different kind of feature from the rest of the list. The others concern how text reads; this one concerns whether a model provider's own provenance signal survives processing. Model vendors have been adding such signals precisely so that machine-generated text remains traceable, and this feature is designed to defeat that mechanism. It is recorded here because it is a documented product capability and users should know it exists. Whether stripping a provenance marker is appropriate depends entirely on what you are doing with the text, and that judgment is not one this page can make for you.
The most defensible use is also the most mundane. If you use a language model to get past a blank page and the result reads like a language model — even, flat, over-hedged, rhythmically monotonous — a rewriting pass can loosen it. Combined with per-sentence alternatives, this is a legitimate editing aid: you are still the author, you are still making every decision, and the tool is proposing options.
The scanner has a use that is independent of the rewriter, and for many people it is the more valuable half. False positives from AI detectors are a documented and serious problem, and people who write in a plain, structured style — or who write in English as an additional language — get flagged disproportionately. Running your own genuinely original work through a scanner before submitting it tells you whether you are likely to face that accusation, which is useful information even if you change nothing.
Teams producing routine copy at volume — product descriptions, category pages, email variants — use tools like this to vary phrasing across many near-identical items. The daily-limit pricing structure is built around exactly this pattern, with the largest published plan permitting 2,000 rewrites per day.
Academic submission is the case that requires an unambiguous answer, and the vendor itself supplies one. The Terms state that StealthWriter is not a cheating tool and must not be used for academic dishonesty or any form of academic misconduct. Submitting machine-generated work as your own violates the integrity policy of essentially every institution, whether or not any detector notices, and the tool's own operator disclaims that use. This is covered further under Limitations, because the surrounding evidence has changed materially and users deserve the full picture.
Work in smaller passages rather than whole documents. Reviewing a rewrite properly requires reading every sentence against the original, and that is not realistic across five thousand words at once — you will start skimming, and skimming is how meaning errors reach publication.
Keep the original. Because rewriting is lossy in ways that are not always visible on first read, you want the source text available for comparison.
Watch numbers, names, and citations with particular care. Rewriting engines are optimised for how text reads, not for whether facts survive. Anything that must be exactly right should be verified character by character after the pass.
Do not treat a favourable score as a finish line. A score is one model's estimate. The evidence below shows how wide the disagreement between detectors can be on the identical passage.
Be honest with yourself about the purpose. If the goal is prose that reads better, this is an editing tool and the tips above apply. If the goal is concealment, the Limitations section explains why that goal is now substantially less achievable than the category's marketing suggests — and why the tool's own terms disclaim it.
Content marketers and copywriters producing at volume, who need phrasing variation and are working with material where a meaning shift is inconvenient rather than dangerous.
Bloggers and independent publishers who draft with AI assistance and want the published result to sound like a person.
Non-native English writers, who are the group most affected by detector false positives. The scanner has genuine diagnostic value here — though the underlying unfairness is a problem with detection, not one a rewriting subscription solves.
Researchers and professionals polishing internal documents, with the strong caveat that technical accuracy must be verified after any rewrite.
Students are the group that needs the clearest warning rather than a recommendation. The vendor's own terms prohibit academic-integrity violations, institutional policies prohibit them independently, and the detection landscape has moved against concealment. The scanner may still be useful defensively — to check whether your own original writing risks being wrongly flagged.
StealthWriter is a web application used in the browser; no desktop or mobile app is documented, and no public API is advertised. Account management happens in the dashboard, which per the changelog now includes billing: You can now open Billing in the dashboard to view your plan, download invoices, and manage your subscription without leaving StealthWriter. Support runs through Intercom live chat, and a contact page handles account, billing, and product questions.
Pricing is published on the homepage rather than a dedicated pricing page — the conventional /pricing and /plans paths both return errors. Plans are metered by rewrites per day rather than words per month, which is unusual in this category and matters if your work is bursty.
| Plan | Monthly | Yearly | Rewrites/day | Scans/day | Words per input |
|---|---|---|---|---|---|
| Free | $0 | — | 10 | 10 | 1,000 |
| Starter | $20 | $200 | 50 | 50 | 5,000 |
| Plus | $50 | $500 | 150 | 150 | 5,000 |
| Pro | $100 | $1,000 | 350 | 350 | 5,000 |
| Scale | $400 | $4,000 | 2,000 | 2,000 | 5,000 |
The free tier is genuinely usable for evaluation: Free ($0) — 10 humanizations/day, with 1,000 words per input. Includes the V2 detector and Deep Scan. Note the input ceiling — the free tier caps at 1,000 words per submission while paid tiers raise this to 5,000, so long documents must be processed in pieces regardless of plan.
Two billing details deserve attention before you subscribe, because they are the source of most documented user complaints. Payments run through a third-party processor: Billing details processed securely by Paddle — we do not store your full payment information. And renewal is automatic: You may cancel your subscription at any time. If you do not cancel before the renewal date, your subscription will be automatically renewed, and you will be charged for the next billing period. A dedicated refund-policy page is referenced in the Terms but does not resolve to a readable document, so the specific refund terms could not be verified. Check the cancellation path inside the dashboard before your first renewal date rather than after.
The category is crowded, and public satisfaction data varies enormously across competitors. Trustpilot ratings for adjacent products at the time of research included Phrasly.AI at 4.7 across roughly 3,000 reviews, Undetectable AI at 3.5 across 961, WriteHuman at 3.9 across 291, and walterwrites.ai at 2.0 across 50 — a spread wide enough that the category average tells you nothing about any individual product.
A serious caution about comparison shopping here: this niche has an unusually corrupted review ecosystem. A search for reviews of any tool in this space returns mostly pages published by competing tools and affiliate sites that earn commission on signups. Such pages routinely conclude that the product being reviewed is adequate but that a different product — the publisher's own, or their highest-paying referral — is better. Rankings and verdicts from these sources should be discounted entirely. Prefer vendors' own documentation for capability claims, general-purpose review platforms for user experience, and your own testing on your own text for quality.
The most consequential alternative is not a competing product at all. If the objective is prose that reads well, ordinary editing — by you, or by a human editor — remains the option that carries no detection risk, no subscription, and no ambiguity about authorship.
This section is longer than usual because the evidence here is genuinely mixed and, in places, directly contradicts how the category markets itself.
The single most useful piece of independent evidence available is a test in which the same AI-generated passage was rewritten by StealthWriter and then submitted to four different detectors. The results did not agree with each other even slightly.
Against one detector, the rewrite failed completely: GPTZero can still tell the text wasn't written by a human. Against another, it succeeded comfortably: StealthWriter was able to bypass Originality AI by a very safe margin. Gaining 88% confidence is a big success for StealthWriter. Two further detectors, Copyleaks and QuillBot, returned 0% AI on the rewritten text.
One passage, four detectors, verdicts ranging from fully detected to fully undetected. That single fact does more to clarify this category than any marketing claim: there is no such thing as text that is undetectable in general. There is only text that a particular model, on a particular day, scores a particular way. Any promise of a 100% human score is therefore unverifiable in principle, because it presupposes a universal standard that does not exist.
An important disclosure about that test: it was published by GPTZero, which sells a competing detector — the one that caught the rewrite. That is a direct conflict of interest, and the conclusion "our detector works and the others do not" is exactly what such a publisher is motivated to find. The reason the test remains useful despite this is that the disagreement itself is the finding, and it does not require trusting any party's accuracy claim. Whichever detector is right, they cannot all be.
The assumption that rewriting reliably conceals machine origin has become substantially weaker. In August 2025, Turnitin announced that its existing AI writing detection capabilities now include AI bypasser detection*, designed to help educators detect text that may have been intentionally modified by AI humanizer tools.
Two qualifications belong with that. First, Turnitin sells detection and has the same incentive to overstate its capability that rewriting vendors have to overstate theirs; its accuracy claims are equally unaudited. Second, trade coverage of the launch recorded a scope limit the press release did not emphasise: Bypasser detection is currently limited to interactions in English. That is a documented boundary on the feature, not an assurance that other languages are safe.
The direction of travel is nonetheless clear. Rewriting tools and detection tools are in an ongoing adversarial cycle, and any specific claim about what evades what is perishable — including every claim on this page.
It is worth stating explicitly that no figure in this domain — vendor or detector — has been verified by a neutral third party. Detection accuracy has been publicly challenged by institutions with no commercial stake. Vanderbilt University disabled Turnitin's AI detection tool for the foreseeable future, and published its arithmetic: applied to the 75,000 papers the university submitted in 2022 at the vendor's own stated 1% false-positive rate, roughly 750 student papers could have been incorrectly labeled as having some of it written by AI.
The implication runs in both directions. Detectors are not reliable enough to be treated as proof of misconduct — and by the same token, a detector reporting "human" is not proof of anything either. Users hoping for certainty from a score will not find it on either side of this market.
The clearest limitation is the operator's own: StealthWriter is not a cheating tool and must not be used for academic dishonesty or any form of academic misconduct. The Terms further place responsibility for institutional compliance entirely on the user.
There is an unresolved tension between that clause and a brand built on the word stealth, and readers are entitled to notice it. What is not ambiguous is the practical position: if you submit rewritten machine-generated text as original academic work, you are violating your institution's policy and acting outside the terms you agreed to, and neither the vendor nor any score will shield you from the consequences.
As established above, the engine rewrites sentences and does not add or remove them. Weak argument structure, poor organisation, and unsupported conclusions pass through untouched.
Public satisfaction data is limited but has a distinctive shape. The Trustpilot profile shows 3.1 Average across 54 reviews, distributed as 5-star 35%, 4-star 2%, 3-star 0%, 2-star 4%, 1-star 59%.
That distribution is more informative than the average. A rating with almost nothing in the middle and majorities at both extremes usually indicates that experience is decided by a binary event rather than by gradual quality differences — and the review text supports that reading. Negative reviews cluster on subscription and charging problems, with one representative complaint stating there is no option to UNSUBSCRIBE OR REMOVE CARD DETAILS, no one responds to either mails or chats, and that charges continued after the plan ended. Positive reviews overwhelmingly praise support responsiveness, frequently naming the same individual agent.
Two contextual notes on this data. The sample is 54 reviews — enough to observe a pattern, too small for confident generalisation. And the platform records that this company hasn't invited customers recently, so reviews may not be representative. That cuts against selection bias from solicited positive reviews, but introduces the opposite skew: unsolicited reviews over-represent people motivated to complain. Read the distribution as a signal about where risk concentrates — billing and cancellation — rather than as a precise measure of satisfaction.
The privacy commitment is favourable as written: Content submitted for AI processing (humanization or detection) is not stored after processing is complete. The policy also states the service is not intended for users under 13 years of age and claims GDPR and CCPA compliance. No third-party audit, certification, or attestation supports any of this, and none is referenced on the site. These are assurances from the operator, and should be weighed as such — particularly if you intend to paste unpublished, confidential, or client-owned material.
Yes, and it does not require a card. The free tier provides 10 rewrites and 10 scans per day with a 1,000-word cap per submission, and includes the V2 detector and Deep Scan. The scanner can also be used on the homepage with no account at all.
No, and no tool can. Independent testing of one passage across four detectors produced contradictory verdicts — detected by GPTZero, undetected by Originality AI, Copyleaks, and QuillBot. Because detectors disagree with each other on identical text, a universal "human score" is not a coherent thing to promise.
The vendor says no. Its Terms state the product is not a cheating tool and must not be used for academic dishonesty, and place compliance responsibility on you. Separately, Turnitin has added detection specifically aimed at humanizer-modified text. Using it to check whether your own original writing risks a false flag is a different matter and does not raise the same issue.
The privacy policy states that content submitted for humanization or detection is not stored after processing completes, and that it is not used for training. This is the vendor's own statement, unaccompanied by third-party audit, so calibrate accordingly for sensitive material.
Free at $0, Starter $20/month, Plus $50/month, Pro $100/month, and Scale $400/month, with annual pricing at ten times the monthly rate. Plans are metered in rewrites per day — 10, 50, 150, 350, and 2,000 respectively — rather than by monthly word volume.
Subscriptions renew automatically unless cancelled before the renewal date. Billing is handled through Paddle, and the dashboard includes a Billing page for viewing plans, downloading invoices, and managing subscriptions. Cancellation difficulty is the most common complaint in public reviews, so locate the cancellation control early rather than at renewal time.
The changelog states the 5.1 model supports major world languages including German, Spanish, Portuguese, French, Italian, Dutch, Chinese, and Japanese. Output quality in these languages is not documented by the vendor and was not independently verified during this research.
Ghost 5.2 Mini is the default lightweight model built for fast rewrites; Ghost 5.2 Pro is tuned for greater coherence and readability. Earlier generations, Ghost 5.1 and Ghost 4.6, remain selectable under a Legacy option.
No. The engine rewrites sentence by sentence without adding, removing, or reordering them, so organisational problems survive the process unchanged. Structural editing has to be done by hand.
StealthWriter is operated by AiVantage LLC, a Wyoming-registered company, with Maher Mansour named as owner. The About page publishes the legal name, email, phone number, and mailing address — a level of disclosure that many products in this category do not provide.
