AI detector for teachers, built to start a conversation
Check a piece of student writing and see exactly which passages raised the score and why. The result is designed to help you decide where to look more closely, not to deliver a verdict on a student.
Drop a document here
PDF, DOCX, ODT, RTF, TXT or Markdown, up to 25 MB
The file is read in your browser. Only its text is sent for checking.
Your report will appear here
Use the result as a starting point
A detector produces a probability. It cannot see how a piece of work was written, and it is wrong often enough that acting on a score alone will, sooner or later, mean accusing a student who did nothing wrong. Several universities have stopped using automated AI detection in misconduct cases for this reason.
What a result can do is tell you which submissions deserve a second look and which passages to ask about. From there, the reliable methods are the ones you already know: compare against the student's earlier work, ask them to talk through their argument, and look at their drafts or document history.
Students most at risk of a false flag
Students writing in a second language are flagged more often, because careful, simple, grammatical prose resembles model output. So are students who have been taught to follow a rigid essay structure, and neurodivergent students whose writing is unusually formal or repetitive. Short answers are unreliable for everyone.
Every result here carries a confidence level and says why it is low when it is. Please read it before reading the score.
A fair process, in practice
Tell students in advance whether and how detection is used. If a submission scores high, share the highlighted report with the student and ask about the specific passages. Give them the chance to show notes and drafts. Decide on the whole picture. Keep the report with your records; the PDF includes the date, score, confidence and highlighted text.
How the AI detector works
An AI detector is a classifier that estimates the probability that text was written by a language model rather than a person. It works by measuring statistical patterns in the writing, not by tracing where the text came from.
Give it something to read
Paste text, drop in a PDF or Word file, or enter the address of a web page. Documents are opened in your browser, so the file itself never leaves your device.
The text is scored
A detection model trained on human writing and on output from AI systems rates the whole text and each sentence for how closely it matches machine writing.
You see the evidence
The report marks every sentence, lists the writing patterns found, and tells you how much confidence the result deserves.
How accurate is AI detection, honestly?
AI detection is accurate enough to raise a question, but not accurate enough to prove an answer. The best detectors catch most unedited AI text with few false alarms, but accuracy drops sharply when text is paraphrased, lightly edited, or written by a non-native English speaker.
Key takeaways
- Accuracy claims of 99% come from the vendors’ own benchmarks.
- One 2026 test of five detectors put the top two at 72% and 74% overall accuracy.
- False positives fall hardest on non-native English writers.
- A score is a probability estimate, not evidence of misconduct.
Reading the score
| Score | Verdict |
|---|---|
| 0–14 | Human-writtenLittle or nothing resembles AI writing. |
| 15–34 | Likely human-writtenMostly reads as a person, with a few AI-like passages. |
| 35–69 | UncertainMixed signals. Not evidence either way. |
| 70–89 | Likely AI-generatedMostly reads as AI, possibly edited by a person. |
| 90–100 | AI-generatedStrong, consistent AI signals throughout. |
A score in the Uncertain range is reported as Mixed when the sentences back that up, with at least 25% of the words in AI-like sentences and at least 25% in human-like ones.
Supported languages: English, French, Spanish, Portuguese, German, Dutch, Polish, Romanian, Italian and Simplified Chinese.
AI Detector for Teachers: common questions
What score means a student used AI?
No score means that. Higher scores make it more likely, and a high-confidence result on a long, unedited text is meaningful evidence. It is still evidence to weigh, not a finding.
Can I check a whole class's submissions?
You can check them one at a time, within the daily allowance. There is no bulk upload.
Is student work stored?
Files are read in your browser and only the text is sent for scoring. We store the resulting scores, not the text, unless you create a share link and choose to include the text. Check your institution's policy before uploading work that identifies a student.
Students can just paraphrase the output. Is detection pointless?
It is limited. Paraphrased text often lands in the Uncertain band. Assignment design does more than detection can: drafts handed in along the way, in-class writing, and questions that draw on class discussion or personal experience.