Related
- HumanFlow vs Undetectable.ai — where we sit against the first of these, including where it beats us.
- HumanFlow vs WriteHuman — and against the second.
- Every humanizer we track, ranked — on published limits rather than on claims.
Undetectable.ai vs WriteHuman
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.
They are not sold in the same unit. Undetectable.ai counts words; WriteHuman counts requests — and a request costs the same whether you spend 600 words on it or 40.
Last reviewed 15 August 2026 · The HumanFlow team
Why people compare these two
Both are established, heavily marketed humanizers at a similar price, so they end up side by side on every shortlist. The comparison is unusually hard to make because the two companies do not publish a number in the same unit, and there is no honest way to convert one into the other without knowing how you write.
That is the whole reason this pair is worth a page. Most comparisons of the two put a price next to a price and stop.
Side by side
| Feature | Undetectable.ai | WriteHuman |
|---|---|---|
| Entry price, monthly | $9.99 | Not published |
| Entry price, billed yearly | $5 | $12 |
| Included at entry | 10,000 words / month | 80 requests / month |
| Per-request cap | No stated per-request cap | 600 words |
| Free tier | 250-word trial | 3 requests / month |
| Free per request | 250 words | 250 words |
Undetectable.ai figures read from their pricing page on 15 August 2026; WriteHuman from theirs on 4 August 2026.
What actually separates them
Undetectable.ai's entry plan is 10,000 words a month with no per-request cap stated on its pricing page. Whatever you paste, it comes out of one pool, and when the pool is empty the month is over.
WriteHuman's entry plan is 80 requests a month, capped at 600 words each. Fill every request to the cap and that is up to 48,000 words — far more than anything at this price. Spend those same 80 requests on 50-word fixes to a paragraph and it is 4,000 words of actual output, which is worse than almost anything at this price. Roughly a twelve-fold spread, decided entirely by working style.
So the plans reward opposite habits. WriteHuman suits someone who writes long and rewrites whole sections; Undetectable.ai suits someone who iterates in small pieces, because a 40-word correction costs 40 words rather than a whole request.
Which to pick
Pick Undetectable.ai if you edit in small pieces, or you want the cheapest annual commitment in the category and can live with a one-time 250-word trial to judge it on.
Pick WriteHuman if you work in long passes and will fill the requests. At 600 words each, eighty of them is more capacity than the price suggests — provided you actually use them that way.
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.