StealthWriter AI Humanizer Review: Limits and Pricing

StealthWriter combines a browser humanizer with a no-account detector. The useful questions are how its daily actions, input cap, free follow-ups, billing, and text workflow fit the job you need to finish.

HumanPen Team

· 28 min read

Is StealthWriter worth trying?

StealthWriter is a practical option when your input is plain text, it fits the plan's per-request limit, and you want several rewrite strengths plus a built-in detector. Its public pages do not establish an editable document-file round trip, a public API, a browser extension, or a future Turnitin result.

I opened the signed-out homepage, FAQ, payment and refund policies, privacy and terms pages, changelog, sitemap, and likely product routes. The date was August 26, 2026. Every input stayed blank; I remained signed out, uploaded nothing, and never opened checkout.

The publisher is HumanPen. Its document workflow appears near the end. Both vendors speak for their own products here; neither set of claims is treated as neutral benchmark evidence.

StealthWriter's most useful public details are not pass-rate claims. They are the two usage meters, the follow-up actions, and the shape of the result.

How do StealthWriter's limits and prices work?

Every plan has at least two limits to track: how many initial actions it allows each day and how many words one input can hold. The homepage publishes monthly prices and daily scan counts through Pro. The FAQ adds annual prices and the Scale plan.

PlanPublic priceInitial humanizations per dayAI scans per dayWords per input
Free$010101,000
Starter$20/month or $200/year50505,000
Plus$50/month or $500/year1501505,000
Pro$100/month or $1,000/year3503505,000
Scale$400/month or $4,000/year2,000Not stated on the checked pages5,000

An April 25, 2026 Changelog entry also lists a Business plan with 800 humanizations per day. Business does not appear in the current homepage or FAQ plan list, and the Changelog does not give its price or scan allowance. The public pages checked here do not show whether Business was discontinued, remains available inside an account, or was omitted from the current list. The table therefore reports the current homepage and FAQ rather than claiming to be a complete catalog.

The FAQ says daily limits reset at midnight UTC. It also says Free usage is subject to fair-use limits that may vary, even though the homepage and plan answer publish ten daily humanizations. If ten runs matter to your schedule, verify the number shown inside the account that day; the card alone is not enough.

A larger daily allowance does not increase the paid-plan input above 5,000 words per request.

What happens after the first Humanize action?

StealthWriter separates the first Humanize action from several ways to revise its result. According to the FAQ, only the initial action reduces the daily humanization allowance.

ActionStarts fromEffect on the published daily humanization count
HumanizeOriginal inputUses one initial action
RehumanizeOriginal input againDoes not reduce the count
Humanize MoreCurrent outputDoes not reduce the count
Re-humanize OutputCurrent output againDoes not reduce the count
Rescan resultCurrent outputDoes not reduce the humanization count

The humanizer offers levels 1 through 10. The FAQ groups 1 to 3 as light changes, 4 to 6 as balanced, and 7 to 10 as heavier rewrites. Free uses Ghost 5.2 Mini, while paid access includes Ghost 5.2 Pro. These are vendor labels, not quality results reproduced here.

After a result appears, the FAQ says a user can click a sentence and choose from up to three alternatives. The page gives no numeric follow-up allowance, and none is added here.

Count the first run, the follow-up controls, and the input size separately. They answer different capacity questions.

What does the built-in detector measure?

The signed-out homepage exposes a separate detector with a 500-word meter and no account requirement. Users can choose V2, the default, or V1. Deep Scan is described as sentence-level color highlighting.

Detector detailWhat the public page statesWhat this review verified
Input size500 words on the homepageThe empty meter displayed `0/500`
Score directionPercentage classified as naturalNo text was scanned
ModelsV2 default, V1 availableBoth controls were visible
Deep ScanSentence-level highlightingThe feature description was visible

That score is StealthWriter's own naturalness estimate. It is not a reproduced Turnitin AI Writing score. The FAQ calls V2 more accurate than V1, but no validation set, detector agreement test, or named Turnitin result was reproduced for this article.

Use the detector as one product control, not as proof of how another detector will classify a submission.

What goes in and what comes back?

The public workflow checked for this review is text-first. The homepage humanizer link goes to sign-up, while the open detector uses a textarea. The FAQ presents pasted text as the starting point, then documents text alternatives in the result.

Public evidenceWhat it supportsWhat it does not establish
Homepage textarea and no file inputA paste-text entry pointSuccessful DOCX, PPTX, or PDF upload
Markdown warning and Remove Markdown optionFormatting may be stripped before a runPreservation of Word styles, fields, or page layout
Up to three sentence alternativesEditable choices inside the web resultA same-format editable file download
No download control before sign-inNo public export route was visibleEvery possible account-only output state

The FAQ recommends plain text for best results when headings, bold text, links, or code blocks are present. That advice is useful for a text workflow, but it also means the public evidence does not support a formatting-preservation promise.

That conclusion stops at the surfaces I could inspect. An account screen could expose something else; the signed-out homepage and FAQ did not show an editable file returning in either DOCX or PPTX format.

A result you can edit in a browser is not automatically the editable document you must submit.

What is available outside the web page?

StealthWriter's FAQ is unusually direct about its current access surface. It describes a browser product rather than a set of integrations.

SurfaceCurrent public statement
WebWorks in modern desktop, tablet, and mobile browsers
APINo public API at this time; one may be offered later
Browser extensionNot available yet; listed as a future roadmap item
LanguagesSpanish, French, German, Italian, Portuguese, Dutch, and others are named

The footer identifies the service as StealthWriter by AiVantage LLC. This review does not transfer features from StealthGPT or any similarly named product.

If an integration is essential, verify the current access route before buying. A roadmap item is not a usable endpoint.

What billing conditions matter before payment?

Price is not the whole purchase condition. StealthWriter's public FAQ and policies also spell out renewal, refunds, and plan changes.

ConditionPublic wording summarized
Free entry$0 and no credit card required
Paid trialNo duration, introductory price, or conversion schedule was published on the checked sales pages
RenewalPaid subscriptions renew automatically unless cancelled before renewal
RefundStandard window: request within 24 hours of purchase or renewal if the account was not used during that period. Exceptional circumstances may be submitted for case-by-case review, but approval is solely at AiVantage LLC's discretion
UpgradeProrated and charged immediately
Lower paid planTakes effect immediately, with no refund for unused time
Move to FreeCancellation is scheduled for the end of the current billing period

The standalone `/pricing` route returned 404 during this check. The current numbers came from the homepage and FAQ. The FAQ uses the account-state word `trialing` in a plan-change answer, but no paid-trial offer or terms appeared on those pages.

Reopen the FAQ and policies before payment. Annual prices and renewal rules can change independently of the homepage cards.

Which jobs fit the public contract?

StealthWriter's checked pages support some jobs more directly than others.

JobFit based on public evidenceReason
Rewrite plain text under the plan limitDirect fitThe FAQ documents paste input, levels, and sentence alternatives
Check up to 500 words without an accountDirect fitThe homepage exposes the separate detector
Process a 12,000-word paper in one runNot supported by the published limitPaid inputs stop at 5,000 words
Return the same editable DOCXWeak public evidenceNo checked page documents that round trip
Call the humanizer from an agent or applicationNot currently documentedThe FAQ says there is no public API at this time
Guarantee a future Turnitin resultNot supportedNo Turnitin benchmark was run or documented here

Before using a real draft, test a disposable passage. Include a number, a citation, a cautious qualifier, and a specialized term whose wording is fixed. Save the source, try the rewrite level you expect to use, and compare every claim before accepting the result.

The Terms and FAQ put compliance with workplace or institutional AI rules on the user, including avoiding misrepresented authorship. Rewriting does not remove disclosure duties from the final work.

Test the exact input, rewrite level, and output handoff you plan to use, not only the product's sample text.

When is a document workflow more relevant?

When the required output is an editable office file, such as DOCX or PPTX, ask for evidence at both ends: which file enters, which file returns, and which passages are allowed to change.

The HumanPen document workflow accepts DOCX and PPTX documents, plus TXT input. The product page states that the returned file keeps its input type and lets the user define scope by passage or from an imported Turnitin report. This article is produced by HumanPen, so these are vendor claims rather than a shared test. Check the returned file yourself.

Eligible results can continue lowering AI for free.

Frequently asked questions

Is StealthWriter free? It has a Free plan listed at $0 with no credit card required. The homepage publishes ten initial humanizations and ten scans per day with 1,000 words per input, while the FAQ separately warns that Free usage is subject to fair-use limits that may vary.

What is StealthWriter's word limit? Free is listed at 1,000 words per humanizer input. Paid plans are listed at 5,000 words per input. The no-account homepage detector has its own 500-word input.

Do the free follow-up actions use another daily humanization? The FAQ says Rehumanize, Humanize More, and Re-humanize Output do not reduce the daily humanization count. It does not state a numeric follow-up allowance.

Does StealthWriter upload and return DOCX files? The signed-out homepage had no file input, and the FAQ documents a paste-text workflow with optional Markdown removal. The checked public pages did not establish an editable DOCX round trip. Account-only states were not tested.

Does StealthWriter have an API or browser extension? The current FAQ says there is no public API and no browser extension yet. It describes both as possible future additions, not current access routes.

Will StealthWriter pass Turnitin? This review cannot support that conclusion. No text was humanized, no detector was run, and StealthWriter's own naturalness score is not a Turnitin report.

Official pages checked

The list below records the public sources used on August 26, 2026. Check them again before relying on a plan or workflow because controls, prices, and policies can change.

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