
Undetectable AI pairs an AI text detector with a humanizer that rewrites flagged passages, plus image, audio and PDF detectors, in one browser-based suite with a Chrome extension and API. Built by a named US team for writers, marketers, students and educators working with AI-assisted drafts.
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Undetectable AI is a browser-based content suite built around an unusual pairing: an AI text detector and a rewriting tool that sit side by side and are meant to be used in sequence. You paste a draft, the detector shows which sentences a classifier would likely flag as machine-written, and the humanizer rewrites those passages. The official description of the mechanism is explicit about this loop — the platform "analyzes your text the same way a detector would, identifying exactly which parts are likely to be flagged," after which "our humanizer rewrites those sections by varying sentence structure, enriching vocabulary, and adjusting tone." The suite has since expanded well past text into an AI image detector, a fake PDF detector, an AI audio detector, an SEO writer and a job application tool.
That pairing is what makes the product worth examining carefully rather than simply describing. A company that sells detection and evasion in the same interface has an unusual position: its detector is the benchmark its own rewriter is optimised against. The commercial promise is stated plainly — rewrites that read naturally "while scoring as human on every major detector" — and that promise is the single claim any prospective user should scrutinise hardest, because it is an assertion about how third-party classifiers built by other companies will behave, made by the party selling the workaround.
Unlike much of this category, the operator is not anonymous. The About page names a full leadership team, with Christian Perry as chief executive and co-founder, Devan Leos as chief communications officer and co-founder, alongside a named chief operating officer and chief marketing officer. That transparency is a genuine point in its favour and makes the product accountable in a way that shell-style competitors are not. It also makes the marketing claims examined below attributable to an identifiable company rather than to a nameless site.
There is a free entry point, but it is tightly bounded: the pricing page states that the "Free Trial is limited to 250 words. Additional usage requires paid plan activation." That is enough to inspect the interface and not enough to assess output quality across a real document, so plan on paying if you intend to evaluate the product seriously.
Paid plans are sold by monthly word allowance. The published tiers list 10,000 words per month at $9.99, 20,000 at $19.00, 35,000 at $31.00 and 50,000 at $42.50, with annual billing advertised at roughly half those monthly rates — the 10,000-word tier, for example, works out at $5.00 per month charged annually at $60.00. Every tier carries the same feature set, including API compatibility, writing level matching, the unlimited Human Auto Typer and unlimited AI detecting; the tiers differ in volume rather than capability. A business track offers custom pricing with non-expiring credits, redistribution and white labelling.
Two caveats belong with these numbers. First, pricing in this category moves: an independent review published earlier recorded paid tiers starting at $14.99 per month for 15,000 words, which does not match the current page — always check the live pricing page rather than any secondary source, this one included. Second, read the guarantee narrowly. It promises that "if anything we produce is flagged as not human, we will refund the cost of humanization" — the cost of that rewriting operation, not the subscription, and explicitly conditioned on the vendor's own flagging determination. Independent review records also show subscription cancellation and unexpected charges as a recurring complaint theme, so treat the renewal terms as something to verify in your own account settings.
Both, in the same interface, and that is the product's defining characteristic. The detector identifies passages a classifier would flag; the humanizer rewrites them. The suite has since added image, audio and PDF detectors, which are purely verification tools with no rewriting counterpart.
That is the vendor's central promise — output that scores "as human on every major detector" — and it is not independently verified. A documented third-party test found rewritten text still flagged as likely AI on re-testing, and the tester published the passage for replication. That tester is a competing detector vendor, so treat both the claim and the rebuttal as interested; no neutral audit of the efficacy claim was found.
The claim appears prominently on the site, but it could not be confirmed here. An independent review states the product was not mentioned in that publication's November 2024 AI detector ranking and that the press quotations on the site are unlinked and could not be located. The quotations carry no source links, so readers cannot verify them independently.
Read your institution's policy before your detector score. Academic integrity rules generally turn on representation rather than detection — one university states that AI-generated material presented as a student's own work is plagiarism "whether paraphrased or copied verbatim," which covers rewritten output explicitly. Separately, Turnitin added detection aimed specifically at text modified by humanizer tools in August 2025.
There is a free trial capped at 250 words. Paid plans are sold by monthly word allowance, listed at $9.99 for 10,000 words, $19.00 for 20,000, $31.00 for 35,000 and $42.50 for 50,000, with annual billing at roughly half those rates. All tiers share the same features and differ only in volume. Pricing has changed over time, so confirm on the live page.
Narrowly: "If anything we produce is flagged as not human, we will refund the cost of humanization." That refunds the specific rewriting operation, not the subscription, and turns on the vendor's own determination. It is not a guarantee against a flagged submission or its consequences.
The review sample is unusually large for this category at 961 reviews, but the 3.5 average conceals a bimodal split of 50% five-star against 41% one-star. The company invites reviews, which introduces selection effects. Self-reported user counts are inconsistent between the vendor's own pages — 24 million on the homepage versus 8 million on the About page — and none of these figures is independently audited.
The official answer is 50 or more, with the vendor itself stating that English is the primary focus and offers the highest accuracy. Note also that the bypasser detection Turnitin announced was trained and tested for English only, so the detection landscape differs substantially by language.
The About page names a full leadership team including a chief executive and co-founder, a chief communications officer and co-founder, a chief operating officer and a chief marketing officer — meaningfully more transparency than most tools in this category offer. On data, the official commitment is that text is never sold, with stricter retention controls presented as part of the business tier rather than the default for individuals.
Yes, several. Screening inbound submissions as an editor, verifying images, audio or PDFs you received, and rewriting your own genuinely authored prose for readability all use the toolkit without presenting machine-generated work as your own. The ethical difficulty attaches specifically to concealment, not to detection or to editing — and the detector half, used as a triage signal followed by human judgement, is the part of this product with the least controversy attached.