The best AI detectors for teachers in 2026

The best AI detectors for teachers in 2026 are the ones that fit your classroom and give you something to discuss with a student beyond a bare percentage. IsThisAiWritten, our own tool, is a free first check that never uploads a student's essay. Turnitin suits schools that already license it. Pangram has the strongest independent accuracy. GPTZero and Grammarly add records of the writing process. Here is how eight options compare, including what each does with student work.

AI detectors for teachers at a glance

Prices at the time of writing (October 2026), in US dollars unless noted. LMS integrations, writing-process evidence and languages are covered under each tool below.

1. IsThisAiWritten

Best for: a free, private first look at a piece of work without uploading a student's text anywhere.

IsThisAiWritten is our own tool. It runs entirely in the browser, so a student's essay never leaves your computer and nothing is stored on a server. There is no account and no length limit, and every word is scanned rather than a sample, so a whole dissertation can go through in one check; .txt and .docx files are read on your device. The report gives an outcome, an AI-likeness score, a sentence map within the text and style explanations, plus a cleaner for hidden characters.

Like any detector, it can be wrong in both directions, so treat a result as a reason to look closer, not as proof, and never use a result, ours or anyone's, as the only evidence against a student. How it is tested is set out on our methodology page.

• Pro: free, no account, and no student data leaves your device.
• Con: English only; no LMS integration.

Price and limits: free; minimum 50 words.

2. Turnitin

Best for: schools and universities that already license Turnitin Originality.

If your institution has it, Turnitin is the path of least resistance: the AI writing indicator appears in the similarity report inside Canvas, Moodle, Blackboard and other LMSs. It is cautious by design. It needs 300 words of prose, shows scores from 1% to 19% only as an asterisk, and Turnitin puts its false positive rate below 1% once a document is more than 20% AI-written. It covers seven languages and, in English, flags text altered by paraphrasers and humanizers. That caution cuts both ways for a teacher reading the report: in a 2026 peer-reviewed study of long papers it wrongly flagged no human work, but it gave fully AI-written papers low scores, so a low score is not a clean bill of health (more in does Turnitin detect AI?).

• Pro: no new tool for staff or students to learn.
• Pro: Turnitin Clarity, a paid add-on, gives students a writing space and you a report on their process.
• Con: not available to individual teachers.
• Con: students cannot see the AI report unless you share it.

Price and limits: institutional pricing only; 300 to 30,000 words per file.

3. Pangram

Best for: teachers who want the most accurate detector available to buy on their own.

If you are buying a detector yourself, Pangram has the strongest independent results, including a 2026 peer-reviewed study of 160 academic papers in which it beat Turnitin, GPTZero and Copyleaks on AI-written, hybrid and humanized work (see how accurate is Pangram). For marking, it connects to six LMS platforms and marks each passage as human, AI-assisted or AI, so you can see when a student used AI for only part of an assignment.

• Pro: strongest independent accuracy, including on humanized text.
• Pro: says it never trains on submitted text.
• Con: no writing-replay or process feature listed.
• Con: keeps scans until deleted; zero data retention is enterprise-only.

Price and limits: Individual is $20 a month or $15 billed yearly for 300,000 words; Team plans are $20 per seat (two seats minimum).

4. GPTZero

Best for: teachers who want writing replay alongside detection.

GPTZero's main classroom feature is writing replay: it can record how a document was written in Google Docs, its own dashboard, Canvas and other editors. When a score is unclear, watching the draft take shape is far more useful than another number. The detector itself rarely flags human writing in independent tests, though humanizer tools fool it more often than Pangram. Batch uploads (up to 250 files on Professional) suit marking a whole class.

• Pro: process evidence and detection in one product.
• Pro: free scans up to 10,000 characters without an account, to try it first.
• Con: Canvas and Google Classroom integration is on the Professional plan.
• Con: keeps a copy of text submitted through its dashboard.

Price and limits: Professional is $45.99 a month or $24.99 billed yearly for 500,000 words; Premium, without LMS integration, is $23.99 or $12.99.

5. Copyleaks

Best for: multilingual classrooms and departments that want AI and plagiarism in one report.

Copyleaks has the broadest LMS list here, detects AI in over 30 languages and combines AI and plagiarism checks in one scan, so a department can run one report instead of two. Its Pro plan includes 25 user seats. On accuracy, Walters' 2023 comparison of 16 detectors rated it near the top, and in the 2026 peer-reviewed study it cleared every human paper but tended to underestimate how much of the other papers AI had written.

• Pro: wide LMS support, many languages, and an "Extra Sensitive" mode meant for humanized text.
• Pro: up to 25,000 characters per scan free, without logging in.
• Con: scans are used for training unless you opt out through support.
• Con: its own false positive figures differ between pages (.03% on the product page, 0.30% on its methodology page).

Price and limits: Personal is $16.99 a month ($13.99 billed yearly) for about 300,000 words; Pro is $99.99 a month ($74.99 yearly) for 25 seats and about 3 million words.

6. PlagiarismCheck.org (TraceGPT)

Best for: teachers on a tight budget who need LMS integration.

TraceGPT is PlagiarismCheck.org's AI detector. It highlights sentences, connects to Canvas, Google Classroom, Brightspace, Moodle, Schoology and Blackboard, and has a Google Docs add-on. AI detection covers English and Spanish only. The company says that across 2,805 human-written documents it wrongly flagged 1.04% of sentences and none at the document level; those are its own tests. PlagiarismCheck was one of the commercial systems in Weber-Wulff's 2023 study, which found the tools tested "neither accurate nor reliable".

• Pro: very low entry price and broad LMS support.
• Pro: accepts long documents, up to 97 pages.
• Con: only two languages for AI detection.
• Con: its AI page says documents are not retained by default, but its privacy policy keeps checked documents until you delete them or your account has been inactive for a year.

Price and limits: AI plans from $2.99 a month; minimum 100 words.

7. Compilatio Magister+

Best for: European schools and universities that want a French-hosted service.

Compilatio is a France-based plagiarism service; AI detection comes with its Magister+ plan for institutions. It integrates with Blackboard, Brightspace, Canvas, Moodle and Microsoft Teams, supports more than 35 languages for AI detection, and hosts data in France. Compilatio claims 94% to 99% accuracy and a false positive rate under 1%. It cites the 2023 Weber-Wulff study, which ranked it second after Turnitin while concluding that none of the tools were accurate or reliable.

• Pro: many languages and EU hosting.
• Pro: teachers can choose whether each document is added to the comparison database.
• Con: institutional sales only, with no public price.
• Con: little recent independent testing of its AI detector.

Price and limits: quoted per institution.

8. Grammarly Authorship

Best for: asking students to show their process instead of relying on a score.

Authorship is not a detector, and that is its value. Students turn it on while they write in Google Docs, Word or the Grammarly editor, and it reports which text was typed, pasted from the web or accepted from a Grammarly suggestion, with a replay. Grammarly lists Canvas submissions among the places it works. It is in Grammarly's free plan, so it costs students nothing.

• Pro: free for students, and it records process rather than guessing.
• Pro: shifts the conversation from accusation to evidence.
• Con: only covers writing done while it is switched on.
• Con: Grammarly trains on individual users' content by default; students can switch this off.

Price and limits: free and Pro plans.

Using any detector fairly

Detector errors fall unevenly, and English learners have carried more than their share since a 2023 Stanford study first put numbers on the problem (see AI detectors and non-native English). Turnitin reports a 1.4% false positive rate for English language learners against 1.3% for native writers in its own testing. Newer tools look much better, but most of that evidence comes from the vendors themselves.

A few habits help: use a detector to decide where to look, not what to conclude; ask for drafts or version history before raising concerns; talk to the student; and agree a written policy on what AI use is allowed. The authors of the 2026 peer-reviewed study put it plainly: detectors "should not be used as sole evidence in high-stakes decision-making".

How we compared

We focused on what matters in a classroom: LMS integration, evidence about the writing process, language coverage, what happens to student work and the price for a teacher buying alone. IsThisAiWritten is listed first because it is our own tool and the free, private option with no length limit; the others are ordered by how well they meet those classroom needs. Between 16 and 18 October 2026 we opened each vendor's integration, pricing, privacy and help pages. Accuracy notes come from independent research, chiefly the 2026 study by Van Vlasselaer, Van Droogenbroeck and Spruyt, the Chicago working paper by Jabarian and Imas, and Walters' 2023 comparison, or are labelled as vendor claims. We did not test these tools on real student work.

Sources

1. Turnitin, AI writing detection capabilities FAQs, checked October 2026
2. Turnitin, Can I purchase an individual Turnitin license?, checked October 2026
3. Turnitin, Turnitin Clarity announcement, checked October 2026
4. Turnitin, AI writing, checked October 2026
5. Pangram, Does Pangram integrate with my LMS?, checked October 2026
6. Pangram pricing, checked October 2026
7. Pangram, Does Pangram train on my data?, checked October 2026
8. GPTZero pricing, checked October 2026
9. GPTZero, Authorship and writing replay, checked October 2026
10. GPTZero, Are you compatible with Moodle?, checked October 2026
11. Copyleaks, LMS integrations, checked October 2026
12. Copyleaks pricing, checked October 2026
13. Copyleaks testing methodology, checked October 2026
14. PlagiarismCheck.org, TraceGPT AI detector, checked October 2026
15. PlagiarismCheck.org privacy policy, checked October 2026
16. Compilatio Magister, checked October 2026
17. Compilatio AI detector, checked October 2026
18. Grammarly Authorship, checked October 2026
19. Van Vlasselaer, Van Droogenbroeck and Spruyt (2026), checked October 2026
20. Jabarian and Imas, Artificial Writing and Automated Detection, checked October 2026
21. Walters, A Comparison of 16 AI Text Detectors, checked October 2026
22. Weber-Wulff et al., Testing of Detection Tools for AI-Generated Text, checked October 2026
23. Liang et al., GPT detectors are biased against non-native English writers, checked October 2026