The shortlist
5 things that do it. Ours is in there, labelled, not on top.
Where one of our products fits, it sits in the list with an "ours" label, never forced to the top. Ours: made by the same studio that runs this site.
AI-text detector for writing and essays, with a Chrome extension.
- Free
- Up to 10,000 words a month, plus the Chrome extension (its own FAQ).
- Paid
- from €9.99 a month (billed annually), Premium
- Best at
- A generous free monthly allowance for checking the odd essay or post.
- The catch
- Prices showed to us in euros, so UK prices may differ; the cheapest paid plan is Premium at €9.99 a month billed annually.
- web
- Chrome extension
AI and plagiarism checker aimed at publishers and content teams.
- Free
- Basic: 3 scans a day, up to 2,000 words a scan, AI detection only.
- Paid
- from $12.95 a month (billed annually), Pro
- Best at
- Checking web content at volume, with Chrome, Google Docs and Firefox add-ons.
- The catch
- The free plan is AI detection only, capped at 3 scans a day.
- web
- Chrome extension
- Google Docs add-on
- Firefox extension
AI-text detector that also checks images and plagiarism.
- Free
- Up to 2,000 words a day and 3 image detection scans a day, no card needed.
- Paid
- from $20 a month (billed annually), Individual
- Best at
- Daily free checks, plus image detection on the free plan.
- The catch
- Paid plans are priced in US dollars, and the cheapest is $20 a month on annual billing.
- web
- Chrome extension
- Google Docs
A free stylometric check: a human-vs-AI confidence score plus which habits read as machine-written.
- Free
- The check itself is free with a free account; no card needed. Humanising toward your own voice is paid, from £12 a month.
- Paid
- from £12 a month, Writer
- Best at
- Showing you why text reads as AI (sentence rhythm, hedging, stock phrases), not just a percentage.
- The catch
- You need a free account to see results, and it is a style check, so it can flag well-edited or second-language writing.
- web
The detector many schools and universities run on submitted work.
- Free
- No individual free tier.
- Paid
- price not checked
- Best at
- Knowing what your institution's checker is likely to say, if you're a student.
- The catch
- You can't buy its AI detection as an individual: Turnitin says it is only available through an institutional or organisational subscription. Its own guidance says results under 20% are less reliable and it needs 300+ words.
- institutional platforms
The same shortlist, as a table
| Thing | Free tier | Paid from | Platforms | The catch |
|---|---|---|---|---|
| GPTZerorel="nofollow noopener" | Up to 10,000 words a month, plus the Chrome extension (its own FAQ). | €9.99 a month (billed annually), Premium | web, Chrome extension | Prices showed to us in euros, so UK prices may differ; the cheapest paid plan is Premium at €9.99 a month billed annually. |
| Originality.airel="nofollow noopener" | Basic: 3 scans a day, up to 2,000 words a scan, AI detection only. | $12.95 a month (billed annually), Pro | web, Chrome extension, Google Docs add-on, Firefox extension | The free plan is AI detection only, capped at 3 scans a day. |
| Pangramrel="nofollow noopener" | Up to 2,000 words a day and 3 image detection scans a day, no card needed. | $20 a month (billed annually), Individual | web, Chrome extension, Google Docs | Paid plans are priced in US dollars, and the cheapest is $20 a month on annual billing. |
| ScriptGrain AI-writing check ours | The check itself is free with a free account; no card needed. Humanising toward your own voice is paid, from £12 a month. | £12 a month, Writer | web | You need a free account to see results, and it is a style check, so it can flag well-edited or second-language writing. |
| Turnitinrel="nofollow noopener" | No individual free tier. | not checked | institutional platforms | You can't buy its AI detection as an individual: Turnitin says it is only available through an institutional or organisational subscription. Its own guidance says results under 20% are less reliable and it needs 300+ words. |
How we checked
What we read, and what we haven't tested yet.
We read each tool's own pricing and help pages on 2 October 2026 and took free allowances and prices from there. We haven't yet run the same samples through every detector, so we make no accuracy claims of our own; any figures vendors publish are theirs, not ours. And every detector gets some human writing wrong. Turnitin aims for under 1% false positives on whole documents, says the rate isn't zero, and adds that results below 20% AI are less reliable and documents under 300 words aren't scored.
If none of these fit
The manual way.
If the stakes are high, like an accusation over coursework, don't rely on any detector. Ask for the draft history (Google Docs version history or Word's) and talk through the work. That shows how it was written far better than a score can.