An AI detector for essays, with a sentence-by-sentence map

Paste an essay below and this AI detector for essays gives you an outcome and a sentence-by-sentence map, free and without an account. There is no word limit, so a dissertation chapter goes in as easily as a 500-word response, and the essay is checked in your browser, never uploaded.

Why use this AI detector for essays

• Free, with no sign-up. No account, no email and no credit card. No credits, no daily cap, no paywall and no premium tier.
• No word or character limit. A short response, a 10,000-word dissertation chapter or a whole thesis goes in as one check.
• Nothing is uploaded. The check runs in your browser, so the essay never leaves your device.
• Your essay is never stored, shared, sold or used to train anything. We never receive it, so it can't end up in any database.
• Every word is scanned, never a sample, so the conclusion gets the same attention as the introduction.
• A report that explains itself: an AI-likeness score, sentence-by-sentence highlights, style notes with one-click plainer wording, and a hidden-character and look-alike-letter cleaner.
• Opens .docx files (and .txt) right in the browser, so there's no need to copy and paste.
• No ads where you paste text.

Preparing an essay for an AI check

A minute of preparation makes the result easier to read, because the check then covers the writer's own prose:

• Remove the title page, the reference list and any appendices. They aren't the essay's own prose, and a bibliography is formulaic by nature.
• Take out long block quotations from sources, so the writer's own sentences are what gets scored.
• Keep the paragraph breaks. The sentence map follows the essay's structure, which makes it easier to see which section a highlighted passage belongs to.

How to check an essay for AI

1. Paste the prepared essay into the box above, or open the .docx file directly.
2. Press Check for AI.
3. Read the outcome with its confidence word, and the reason given for it.
4. Look at the AI-likeness line, which reads “more AI-like than X% of human writing we tested”.
5. Open the sentence map and read the highest-scoring passages in context. They are ranked against the rest of this essay, which tells you where to look first.
6. Go through the style notes, and keep a copy of the result if you need one: print it, save it as a PDF or download it as JSON.

Reading Human, Mixed, AI and Inconclusive on an essay

Human means the essay didn't clear the AI cut-off. Mixed means at least one substantial passage, around 120 words or more, scored as AI while the rest didn't. On an essay that sometimes lines up with a pasted-in paragraph, and sometimes with the most formal section, such as a summary of the literature; the sentence map shows you which passage it is. AI means most of the text scored as AI and the overall score cleared the AI cut-off. Inconclusive means the evidence pointed both ways, and the detector tells you so, with its reason, rather than forcing a verdict.

Style notes: plainer wording in one click

Essays pick up stock phrasing easily, whoever writes them. The style notes mark phrases such as “it is important to note” and “plays a crucial role”, words such as “delve”, “pivotal” and “showcase”, and em dashes. Each note explains why it was marked, and where a plainer wording is safe the report offers it as a one-click fix: “note” in place of the whole “it is important to note”, “matters” for “plays a crucial role”, “key” for “pivotal”. You can edit the essay in place, undo any change and press Re-scan to check the new version. Style notes are writing help only and never feed the verdict, so they are worth a look on any essay, flagged or not.

Long essays, dissertations and theses

A word cap would mean splitting a dissertation into chunks and piecing several separate results together. Here there is no cap: the whole document goes in at once and every word is scanned. Chapters are found from their headings, so a thesis gets a result for each chapter, and a chapter jump menu takes you straight to any of them. The long documents page has more on checking a full thesis.

For students and for markers

If you're a student checking your own work, the report shows how your essay reads and which passages stand out, before anyone else sees it. Keep your drafts and version history alongside it: together they are a clear record of how you wrote the essay. The students page covers what to do with each result.

If you're marking, the sentence map gives you specific passages to discuss with a student, alongside their drafts and how well they can talk about the material. The teachers page has a workflow for that conversation, and our post on being wrongly flagged covers it from the student's side. The methodology page explains how the detector is tested.