How to check if a student used ChatGPT in Google Docs

Why the revision history beats a detector score

A detector reads the final text and estimates how "AI-like" it is. That produces false positives on clear, formulaic or non-native writing, and false negatives on lightly paraphrased AI output. Worse, a score gives you nothing to show the student or a parent. It's a number from a black box.

Google Docs records every insertion and deletion with a timestamp. When a student types an essay, the history shows sentences appearing a few characters at a time, with pauses, deletions and rewrites. When a student pastes in ChatGPT output, the history shows a paragraph, or the whole essay, appearing in a single instant. Those two histories look nothing alike, and either one can be replayed for anyone to see.

Three signs of pasted AI text in a replay

1. Large instant insertions. Hundreds of words appear at once. Checked4AI flags these paste events in the timeline so you don't have to scrub for them.
2. Almost no revision after the paste. Human drafts get edited. Pasted text tends to sit untouched apart from a few cosmetic tweaks to the introduction.
3. Compressed timing. A 1,500-word essay that took eleven minutes from blank page to final period was not composed in that window.

Checked4AI condenses these into a single Natural Typing score from 0% to 100%, built from the delete ratio, keystroke timing variation and paste volume. Scores from 70% up are consistent with organic drafting. Scores under 40% mean the document arrived mostly in pastes, and the replay is where to look next.

How to check a student's Google Doc

1. Install the free Checked4AI Chrome extension and sign in with your school Google account.
2. Open the student's document. Anything submitted through Google Classroom, or shared with you with edit access, works.
3. Click the Checked4AI button in the Docs toolbar. The extension syncs the revision history through the Google Drive API and opens the viewer in a new tab.
4. Read the Natural Typing score and scan the session timeline. Each writing session shows when it happened and how much text it added.
5. Press play. Watch at 1× for a specific passage, or 10× to see the shape of the whole essay in under a minute.
6. If something looks off, jump to the flagged paste event and watch the seconds around it.

The auto-typer problem

Students know about revision history now. The workaround circulating on TikTok and Reddit is an "auto-typer": a script or extension that takes pasted AI text and types it into the document one character at a time so the history looks organic. To a plain replay tool it does look organic.

Human typing is irregular. We speed up on familiar words, pause before hard ones, and backspace constantly. Scripts produce timing that is far too uniform. Checked4AI's auto-typer detection (Pro) analyzes inter-keystroke timing and flags the robotic rhythm that scripted typing leaves behind, even when the replay itself looks fine.

Two signals are better than one

Typing patterns tell you how a document was assembled. They don't tell you what the text reads like. Checked4AI's AI Content Check runs on the document text and returns an AI-generated likelihood with a one-sentence explanation. Pro subscribers see it automatically alongside the typing analysis; free users can paste a passage into the checker.

When both signals agree, you have a strong case in either direction. When they disagree, for instance a high AI likelihood on text that was clearly typed and revised over three sessions, the typing evidence usually wins, because it's a record rather than an estimate. That's also the situation where a detector alone would have produced a false accusation.

Talking to the student

The replay is most useful as the start of a conversation, not the end of one. Export the replay as a video (Pro) or open it in front of the student and ask them to walk you through how they wrote it. Students who did the work can narrate their own drafting. Students who didn't usually can't, and the recording spares everyone an argument about a percentage.

For the student's side of this situation, see what we tell students who've been accused of using AI. Pointing a wrongly flagged student to their own revision history is often the fastest way to resolve a case.

Privacy and student data

Revision data is stored only in your browser. Document text leaves the browser only when an AI check runs, and it is not stored afterwards. Checked4AI activates only on docs.google.com and reads nothing from other sites. Full details are in the privacy policy.