Head to head · QuillBot

QuillBot vs Undetected AI: a paraphraser and a humanizer are not the same tool

The short answer

QuillBot and Undetected AI solve different problems. QuillBot is a paraphrasing and grammar suite: it reword sentences, fixes writing, and now bundles a humanize feature, all for $8.33 a month billed yearly (July 2026). Undetected.ai does one job, rewriting AI text so it clears GPTZero, Turnitin, Originality.ai, Copyleaks, and ZeroGPT, and shows each detector passing. If you want an all-round writing assistant, QuillBot is excellent value. If the actual job is beating detection, a paraphraser is the wrong tool, and independent tests keep showing QuillBot-style paraphrased text still getting flagged.

Last updated July 2026 · Pricing read off each vendor's own page

The Humanizer

5 detectors live

Paste your AI-written text

Try:

Tone

Strength:

Your text is never stored or used to train models.

Cleared. Reads 100% human.

Before · flagged as AI

After · reads human

Compare pricing

Meaning kept · 5 detectors, one pass · Never stored or used for training

QuillBot is one of the most popular writing tools on the internet, and deservedly so. It paraphrases, checks grammar, summarizes, generates citations, and, more recently, offers a humanize feature inside the same subscription. For general writing help it is hard to beat at the price.

The confusion starts when people reach for QuillBot to beat an AI detector. Paraphrasing and humanizing sound like the same thing, but they change different properties of your text, and detectors measure the properties paraphrasing leaves untouched. This page compares the two tools honestly: what each is built for, the real July 2026 pricing, and which one actually clears a detector.

Verified pricing

QuillBot vs Undetected.ai pricing

QuillBot prices read off quillbot.com in July 2026. QuillBot bills the whole suite as one subscription rather than a per-word humanizer plan, so the tiers below are not a like-for-like word-pool comparison. Check their page for the latest.

Plan level	Undetected.ai	QuillBot
Entry plan	Starter: 15,000 humanized words/mo at $9/mo billed yearly ($12 monthly)	Premium: $8.33/mo billed yearly ($99.95/year); $19.95 month-to-month
What you get	A focused humanizer tuned against five detectors, with per-detector proof	Full writing suite: paraphraser, grammar, summarizer, citations, plus a humanize feature
Higher volume	Pro 80,000 words/mo ($19); Unlimited words ($39/mo billed yearly)	One flat Premium price; a Team plan for shared billing (contact QuillBot)
Free usage	No free tier; the on-page demo shows the rewrite and gauge	Free plan: 125 words per paraphrase, limited humanize, 2 of 9 modes

Prices change and promos expire. Always confirm on each vendor's pricing page before buying.

Side by side

What each tool actually does

A fair look at where each one wins. Both are capable humanizers; the fit depends on your volume and workflow.

What matters	Undetected.ai	QuillBot
What the tool is built to do	Rewrite AI text so it reads human and clears detectors	Reword and improve writing; humanizing is a newer add-on feature
Detector-clearing focus	The entire product is tuned against GPTZero, Turnitin, Originality.ai, Copyleaks, ZeroGPT	Paraphrasing preserves the structure detectors measure; results vary
Proof the text will pass	Live gauge plus a pass badge for each of the five major detectors	A human-score reading from QuillBot's own in-house detector
Long documents	Paste the whole draft and humanize in one pass	Paraphrase works sentence by sentence; long text is fine but stays structurally similar
Everyday writing help	Not the job; this is a humanizer only	Genuinely strong: grammar, tone, summaries, citations in one place
Best suited for	People whose specific goal is clearing AI detection	Writers who want an all-round assistant and treat humanizing as a bonus

Paraphrasing and humanizing change different things

A paraphraser swaps words and reshuffles clauses while keeping the meaning. "The results demonstrate a clear improvement" becomes "the findings show a distinct enhancement." Different vocabulary, same sentence length, same clause order, same rhythm.

AI detectors do not keep a list of banned words. They measure how predictable your text is and how much your sentence structure varies. Synonym substitution barely moves either number, which is why detectors flag paraphrased AI text so often. A humanizer built for the job changes the structural properties detectors actually read: the sentence-length variation, the rhythm, the predictability. That is a different operation from swapping in a thesaurus, and it is the operation that clears a scan.

Does QuillBot bypass AI detection?

Not reliably. QuillBot\'s core paraphraser preserves the structure detectors measure, so paraphrased AI text frequently still scores as machine-written on GPTZero, Originality.ai, and Turnitin, which explicitly markets a paraphrase-detection signal. QuillBot has added a dedicated humanize feature that performs better than raw paraphrasing, but the tool does not center its product on clearing external detectors, and it does not show you each detector passing.

There is also a conflict worth naming: QuillBot sells its own AI detector. A company that scores text for AI is a fine writing assistant, but it is not structured around the single goal of getting your text past the five detectors a teacher, editor, or client is most likely to run.

Where QuillBot is genuinely the better buy

For most writing tasks that are not about beating detection, QuillBot is excellent and, at $8.33 a month billed yearly, a lot of tool for the money. If you want one subscription that paraphrases, fixes grammar, summarizes long documents, and generates citations, QuillBot does all of it well, and its humanize feature is a reasonable bonus for light needs.

Undetected.ai does not compete on that breadth. It is a humanizer, full stop. The two are complements more than rivals: draft and polish in QuillBot, and when a piece has to clear a detector, run it through a tool built for exactly that. If your only reason to subscribe is passing detection, pay for the specialist rather than the suite.

The honest split

Who should pick which

Pick Undetected.ai if

Your specific goal is clearing GPTZero, Turnitin, Originality.ai, Copyleaks, or ZeroGPT
You want to see each detector pass, not read one in-house human score
You would rather a tool built for detection than a paraphrase feature inside a writing suite

Pick QuillBot if

You want an all-round writing assistant: grammar, paraphrase, summarize, cite
Beating detectors is a nice-to-have, not the reason you are paying
One flat suite price for unlimited paraphrasing fits how you work

No tool wins every workload. Test both on your own text before committing to a year.

Good questions

QuillBot vs Undetected.ai, answered

Not reliably. QuillBot's paraphraser rewords text but keeps the sentence structure detectors measure, so paraphrased AI writing often still gets flagged by GPTZero, Originality.ai, and Turnitin, which specifically looks for paraphrased text. QuillBot's newer humanize feature does better than plain paraphrasing, but the tool is not built around clearing external detectors.

As of July 2026, QuillBot Premium is $19.95 a month month-to-month, or $8.33 a month billed yearly ($99.95 a year), which unlocks unlimited paraphrasing, all writing modes, and the humanize feature. The free plan caps paraphrasing at 125 words and offers limited humanizing.

Undetected.ai, because it is built for that one job: it rewrites AI text against all five major detectors and shows each one passing. QuillBot is a stronger all-round writing suite, but paraphrasing preserves the structural signals detectors read, so it clears scans less reliably and gives you no per-detector proof.

Keep comparing

More head-to-head comparisons

vs Undetectable AI

Try Undetected.ai on your own text

Paste your text, watch the detection gauge flip from red to green, and see meaning-preserving prose clear all five detectors before you copy.

See pricing