A free Chrome extension that lets a teacher replay how a student's Google Doc was written.
Made by Mr. Hafiz, a high school teacher in Toronto.
Open a Google Doc you can edit, click Replay writing, and watch the document appear from a blank page. You can see what was typed and what was pasted, when each passage was written, what was deleted, and how long the writing took. You can save a PDF summary.
A paste does not prove a student copied something. Students often draft in another app first. Doc Replay is meant to start a conversation, not to settle one.
It is free. If it saves you time, there is an optional tip link inside the extension.
Doc Replay is not affiliated with or endorsed by Google. Google Docs is a trademark of Google LLC.
Last updated: October 23, 2026
What Doc Replay reads: When you click Replay writing, the extension reads the edit history of the Google Doc you have open, using your own Google sign-in. Google only shares edit history with people who can edit the document.
What it does with it: The history is worked out inside your browser. It is not uploaded, sent to me, or shared with anyone. I do not run a server for Doc Replay, and I cannot see your documents.
What it stores: Doc Replay saves two small things on your own computer, in your browser's storage for docs.google.com: your display settings (for example playback speed) and any names you give to editors (for example Student). They stay on your computer. Clearing your browser's site data removes them.
What it does not do: It does not collect personal information, show ads, track you, or use analytics. It does not run on any website except Google Docs.
Files you make: If you export a PDF, copy a summary or save a raw history file, those go to your own downloads or clipboard. They may contain a student's writing, so please keep them private and follow your school's rules.
The tip link: The extension has an optional Support this tool button. It does nothing until you click it. It then opens my Buy Me a Coffee page in a new tab. That site has its own privacy policy. Nothing from your documents is sent there.
Students and children: Doc Replay processes a student's writing only on the teacher's computer. Teachers are responsible for using it in line with their school's and board's privacy rules.
Changes: If this policy changes, I will update the date above.
Contact: mrhafizedu@gmail.com