An AI detector for writers, novelists and freelancers

Writers often have to answer to detectors they don't control: a client's checker, a magazine's screening, an editor's hunch. IsThisAiWritten is a free AI detector for writers that takes a whole manuscript at once and shows which passages read most like AI, without your draft ever leaving your computer. Paste a draft below, or open the file.

Why writers check here

• 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 pitch, a feature or a whole novel goes in as one check.
• Nothing is uploaded. The check runs in your browser, so an unpublished manuscript never leaves your device.
• Your writing is never stored, shared, sold or used to train anything. We never receive it.
• Every word is scanned, never a sample.
• A report that explains itself: an AI-likeness score, sentence-by-sentence highlights, style notes with one-click plainer wording, a hidden-character and look-alike-letter cleaner, and a narrative fingerprint for fiction.
• Opens .txt and .docx files right in the browser.
• No ads where you paste text.

Why a writer would check their own work

A freelancer may have a piece bounced because a client's tool flagged it. A novelist sending pages to agents may wonder whether a clean, heavily edited manuscript will look machine-made. A ghostwriter may want to know before the client asks. In each case you already know who wrote the words. The useful question is which parts of the draft a detector might pick on, and why, and this report answers it passage by passage.

What an AI detector for writers should show you

Beyond the outcome and its confidence word, four parts of the report are useful when the writing is your own:

• Sentence map. Each sentence is shaded relative to the rest of your text, so you can see whether the higher scores sit in one section (often the most polished or most formulaic) or spread across the piece.
• Style notes. Stock phrasing, AI-favoured words and em dashes, each highlighted and explained, with a plainer wording you can apply in one click where one fits. They are not part of the verdict, so treat them as a quick read on habits an editor might notice too, and accept only the changes you agree with.
• Narrative fingerprint. For fiction, features of your manuscript such as dialogue share, smell imagery and how often the narrator explains what a scene means, set beside human and AI base rates from the StoryScope study.
• Invisible-character cleaner. Zero-width characters and look-alike letters can slip in when text is pasted from the web or from other tools. The cleaner shows them and gives you a clean copy.

How to check a draft or manuscript

1. Export the draft as .docx or .txt, or copy all of it. Keep chapter headings on their own lines.
2. Paste the text or open the file in the box above. Length doesn't matter: a 208,000-word novel has been checked in one go.
3. Press Check for AI and read the outcome with its confidence word.
4. For a book, switch to the chapter view to see whether any chapter stands apart from the rest.
5. Read the passages that score highest and decide, as the writer, whether anything needs changing. Edit in place and press Re-scan to see the new version.

Edit for readers, not for a score

Once you see a flag, it's tempting to strip out every em dash or rough up tidy sentences. Resist it. Em dashes and lists of three were human habits long before language models copied them, and they prove nothing either way (more in em dashes don't prove AI). Use the style notes the way you'd use a sharp copy editor: take the plainer wording where it makes the sentence better, and leave your voice alone where it doesn't.

A paper trail is your strongest protection. Keep dated drafts, your document's version history, research notes and any correspondence about the piece. If a client or editor questions your work, those show how it was made.

A report you can send a client

If a client's checker has flagged your piece, run it here and send them what you find. The report can be saved as a PDF, printed, downloaded as JSON or copied as a short summary for an email. The sentence map and style notes give you specific passages to talk about, together with your drafts, which makes for a quicker and calmer conversation than arguing over a single score.

Privacy for unpublished work

Because the detector runs in your browser, an unpublished manuscript or an embargoed article never reaches us or any third party. There is no account and no stored history of what you checked. If you want to see that for yourself, the private AI detector page shows how to watch the network traffic in your browser's developer tools. The methodology page explains how the detector is tested.