Related
- HumanFlow vs QuillBot — where we sit against the first of these, including where it beats us.
- HumanFlow vs Grammarly — and against the second.
- Every humanizer we track, ranked — on published limits rather than on claims.
QuillBot vs Grammarly
HumanFlow is not one of the two tools on this page. We make a competing product, so weigh this accordingly — our methodology sets out how we source competitor figures and what we refuse to claim.
Neither of these is a humanizer. Both are writing suites that added one, and it shows in how the limits are drawn.
Last reviewed 15 August 2026 · The HumanFlow team
Why people compare these two
This is the comparison people make when they already pay for one of them. Both are established writing tools with large existing user bases, both added AI humanizing to a product bought for something else, and both offer it free — so the question is rarely "which should I buy" and usually "is the one I already have good enough".
It is also the pair where the framing matters most. Comparing either against a dedicated humanizer is comparing different products; comparing them against each other is at least like for like.
Side by side
| Feature | QuillBot | Grammarly |
|---|---|---|
| Entry price, monthly | Not published | $30 |
| Entry price, billed yearly | $8.33 | $12 |
| Included at entry | Unlimited paraphrasing and unlimited AI Humanizer | 2,000 AI prompts a month — not metered in words |
| Per-request cap | No cap stated on Premium | No stated word cap |
| Free tier | 125 words per paraphrase; humanizer 125 words, 6 uses a day | Free humanizer and free AI detector, no account needed |
| Free per request | 125 words | No stated word cap |
QuillBot figures read from their pricing page on 4 August 2026; Grammarly from theirs on 4 August 2026.
What actually separates them
QuillBot's constraint is the per-use cap. Its free paraphraser stops at 125 words per use, which is a paragraph, and the humanizer works the same way — so a 1,500-word essay is twelve separate passes on the free tier.
Grammarly's constraint is a different unit entirely. Its paid plan is metered in AI prompts rather than words — 2,000 a month — and its free humanizer and standalone AI detector require no account at all. There is no published per-scan word cap to plan around, which is convenient until you need to predict what a long document will cost you.
Grammarly is also unusually direct about the boundary. Its documentation states the humanizer "is not intended to bypass AI detectors", and warns that using one to disguise AI use "may be considered unethical and could constitute cheating or plagiarism". Very little else in this category says that.
Which to pick
Pick QuillBot if you want paraphrasing and rewriting as the main event and will work within a per-use cap, or you want the cheapest annual entry of the two at $8.33 a month.
Pick Grammarly if you want the grammar and clarity tooling as well, you write in more than one language, or you want a free humanizer and detector with no account — and you are comfortable with an allowance measured in prompts rather than words.
The claim we won't compare on
Neither tool's ability to get text past an AI detector appears above, and it is not an oversight. No vendor can observe or control the systems such a claim is about, detectors change without notice and disagree with each other on identical text, and every published bypass rate in this category was produced by the company selling the tool it tested. We publish none for our own product either — see why we publish no bypass rates.