The best AI detectors in 2026
Nine detectors, listed A to Z, with the same warning attached to all of them: none of these is proof, and the good ones say so themselves.
Start with the part every vendor's marketing page skips. AI detection is probabilistic, it is least reliable exactly where it is most often used — short passages and non-native English — and there is a well-documented tendency across the whole category to flag second-language writers as machines. A detector's output is evidence for a human judgement, not a verdict.
With that said, the tools differ enormously in what they are for. Some are institutional systems of record with case workflows and appeals; some are a box you paste a paragraph into; one is a hotkey. Ranking them against each other would be meaningless, so they are listed alphabetically with the situation each is built for.
The list below is in alphabetical order, not ranked. aiCat is one of the tools in it, so any ranking we published would be worth what you would expect — instead, every entry says plainly which situation it is the right answer for, and which it is not.
What was actually compared
- What the tool does when the sample is too short to judge
- Whether the reasoning behind the score is shown or hidden
- Whether the result has to survive being challenged by the person it is about
- Character and document limits
- Whether you paste the text somewhere or check it where it is
All 9, A to Z
| Tool | Price from | What it is | Languages | Strongest at |
|---|---|---|---|---|
| aiCat | Free · Premium from $6/mo | Every app, OS-wide | Any language the model speaks | One key that proof-reads, translates, explains, detects, dictates and reads aloud |
| ChatGPT | Free · Plus from $20/mo | Chat assistant | Multilingual | General reasoning that is still at or near the top of the field; Long, open-ended sessions where the task changes as you go |
| Copyleaks | Free (limited) · from ~$10/mo | AI and plagiarism detector | Multilingual | Plagiarism and AI detection in one product; Wider language support than most detectors |
| GPTZero | Free (limited) · from ~$15/mo | AI detector | English-first | Detection as a dedicated product, with sentence-level highlighting; Bulk scanning of many documents at once |
| Originality.ai | Credits from ~$30 · subs from ~$15/mo | AI detector | English-first | Aimed at publishers and agencies checking commissioned work; Combined AI detection, plagiarism and readability in one scan |
| Sapling | Free · Pro from ~$25/mo | Business writing assistant | Several, English strongest | Built for customer-facing teams: CRM and helpdesk integrations; Autocomplete and snippet expansion for repeated replies |
| Turnitin | Institutional licence | Academic integrity platform | Multilingual | The established system of record for academic integrity; Similarity checking against an enormous private corpus |
| Winston AI | Free trial · from ~$12/mo | AI detector | English, French, Spanish, German | Detection with per-sentence breakdowns and printable reports; OCR, so scanned and handwritten work can be checked |
| ZeroGPT | Free · from ~$10/mo | AI detector | Multilingual | Free and instant, with no account for the basic check; Simple enough that anyone can use it once |
The list, A to Z
aiCat
The check you make about something already on your screen
Why: Select the passage, press the key, and get a likelihood with the exact phrases that produced it. It refuses samples too short to judge instead of returning a number you would half-believe. Free to start, Premium from $6/month.
Watch out: No reports, no bulk scanning and no audit trail — nothing here is built to survive being contested.
Download for free →ChatGPT
Not a detector, and worth saying so
Why: It will give an opinion on whether text reads as machine-written, and that opinion is sometimes useful as a second read alongside a real detector.
Watch out: It has no detection model behind it and no calibration. Do not treat its answer as a score.
aiCat vs ChatGPT →Copyleaks
Detection and plagiarism as one scan, in more languages than most
Why: Wider language support than the English-first detectors, source-code checking as well as prose, and the LMS and API integrations an organisation needs.
Watch out: Enterprise-shaped: pricing and onboarding assume an institution. Upload and scan, from about $10/month.
How aiCat's detection works →GPTZero
The one to use if the result might be argued with
Why: Sentence-level highlighting, exportable reports, LMS integrations, and a vendor that has been unusually public about what detection cannot prove.
Watch out: Paste or upload, character caps on lower tiers, and paid plans start from about $15/month.
aiCat vs GPTZero →Originality.ai
The one built for commissioning work from other people
Why: Aimed at publishers and agencies: AI detection, plagiarism and readability in one pass, team seats, shared scan history, and published benchmarks.
Watch out: The credit model makes casual checking feel expensive, and it carries the same non-native-writer bias as the rest of the category.
How aiCat's detection works →Sapling
Detection as one feature of a support-team product
Why: Well-regarded as a detector, but it arrives attached to autocomplete, snippets and CRM integrations — which is the reason most teams end up with it.
Watch out: Priced for teams from about $25/month, and the value drops sharply outside the integrations.
How aiCat's detection works →Turnitin
The system of record, if you are an institution
Why: Similarity checking against a corpus nobody else has, deep LMS integration, and reporting built to withstand an appeal.
Watch out: You cannot buy it as an individual and there is no published price.
How aiCat's detection works →Winston AI
The one for a teacher rather than an institution
Why: Per-sentence breakdowns, printable reports, plagiarism in the same subscription, and OCR so scanned and handwritten work can be checked.
Watch out: Four languages, word quotas on lower tiers, and paste-or-upload only. From about $12/month.
How aiCat's detection works →ZeroGPT
The free one, for the question that does not matter much
Why: Instant, no account for a basic check, several languages, and a cheap paid tier if the volume grows.
Watch out: Less published methodology than the research-led detectors. Fine for a hunch, not for a decision.
How aiCat's detection works →Hands-on notes
First-person impressions from using these, not a benchmark. They are here because everything above this point is a table, and a table cannot tell you which tool you will still be opening in three months.
I check maybe a dozen things a month — an outreach email that reads oddly, a review that is too fluent, a submission. What made this the one I actually use is that the check happens where the text already is, and that it declines to answer on anything short instead of giving me a number I would have half-believed. The onboarding was quick and the pleasant surprise was elsewhere: the same key that scores a passage will also read it aloud or translate it, and it remembers the context of what I am working on well enough to be useful without being asked. It is an app you download, which is the trade — if you would rather have an assistant living on your machine than a website you paste into, that is the deal.
The one I would still use if a result had to go anywhere official. The sentence-level highlighting is genuinely informative and the vendor has been more publicly honest about the limits than most. It is also a website you paste into, which for a one-off check is fifteen seconds you notice.
Bought a credit pack to check commissioned articles. It is clearly built for exactly that and the combined plagiarism-and-AI scan in one pass is the right shape for an editor. The credit model does make you think twice about casual checks, which is either discipline or friction depending on your mood.
Free, instant, and fine for the question 'is this obviously generated'. I would not put its output in front of anybody who might argue with it.
One of them is a hotkey. Try it on the text you have open
Free to start with 10 aiCatCoins, no card. Premium starts from $6/month. macOS, Windows and Linux.
aiCat pricing at a glance
| Plan | Price | aiCatCoins / month | Max selection | What it unlocks |
|---|---|---|---|---|
| Free | $0 | 10 | 500 chars | Everything aiCat does, plus free dictation and your own memory |
| Premium | from $6/mo (list $10) | 3 000 | 5 000 chars | Think More, read-aloud, encrypted memory, premium models |
| Team + Offline | from $18/member | 12 000 | 50 000 chars | Edit your memory, MCP access, local models, team sync |
| Enterprise | from $90/member | 150 000 | Unlimited | SSO, audit, best coin rate |
Shortlist of one? Start with the one that costs nothing to try
aiCat's free tier includes every task, 10 aiCatCoins a month, and coins bought outright never expire. macOS, Windows and Linux.
Frequently asked
Can any of these prove text was written by AI?
No. Every one of them returns a likelihood. A high score is a reason to look more closely, ask questions, or request a draft history — it is not an answer on its own.
Why do detectors flag non-native writers?
The signals detectors use — even sentence length, limited vocabulary variation, careful punctuation, few idioms — describe a great deal of competent second-language writing as well as they describe model output. It is the category's central unsolved problem.
What should a teacher or editor actually do with a high score?
Treat it as a prompt for a conversation, not a finding. Ask for the drafting history, ask the writer about their choices, and use a tool with an audit trail if the outcome could be contested.
Which operating systems does aiCat support?
macOS (Apple Silicon and Intel), Windows 10/11, and Linux as AppImage, .deb or .rpm.
Is my text sent anywhere?
Only the text you explicitly act on is sent to the model you selected, for that one request. Your history is stored locally on your device. Team + Offline can run a local model so nothing leaves the machine at all.