Watchmarker for Youtube

Name: Watchmarker for Youtube
Rating: 4.43 (149 reviews)
Author: sniklaus

Automatically mark videos on Youtube that you have already watched.

As of June 2026, Watchmarker for Youtube has 10,000 users and a 4.43/5 rating from 149 reviews in the Productivity category.

sniklaus Productivity★ Featured

Chrome Web Store ↗.crx

Users+25.0%

10.0K

10,000

Rating+0.5%

4.43

149 reviews

Reviews+3.5%

149

Version

5.1.0

Manifest V3

90-day change · In the last 90 days this extension gained 2.0K users, 1 version update, changed permissions.

History

8 snapshots

Tracking since Apr 19, 2026.

View as table

Date	Users	Rating	Reviews	Version
Apr 19, 2026	8.0K	4.41	144	5.0.4
Apr 24, 2026	9.0K	4.41	145	5.1.0
Apr 29, 2026	8.0K	4.41	145	5.1.0
May 4, 2026	8.0K	4.42	146	5.1.0
May 12, 2026	10.0K	4.42	146	5.1.0
May 30, 2026	10.0K	4.42	147	5.1.0
Jun 3, 2026	9.0K	4.42	147	5.1.0
Jun 14, 2026	10.0K	4.43	148	5.1.0
Now	10.0K	4.43	149	5.1.0

Changelog

Apr 19, 2026

permissions

alarms, cookies, declarativeNetRequest, declarativeNetRequestWithHostAccess, history, scripting, storage, tabs

alarms, cookies, declarativeNetRequest, declarativeNetRequestWithHostAccess, history, scripting, storage, tabs, webRequest

Permissions & access

Permissions: alarmscookiesdeclarativeNetRequestdeclarativeNetRequestWithHostAccesshistoryscriptingstoragetabswebRequest
Host access: *://www.youtube.com/*, *://m.youtube.com/*

Screenshots

About

Youtube keeps track of your watch history and automatically marks videos that you have already watched. They however only mark recently seen videos, which is kind of disappointing. This addon fixes this issue and keeps track of your entire watch history, such that not only the recently seen videos are being marked.

***How can the persistence of the database be ensured?*** There is an export and import feature, which makes it easy to create a backup of the history. This backup can  easily be archived such that you can ensure that you never lose your history.

***How can I make sure that the database is complete?*** The automatic synchronization only considers the recent activity. You are thus encouraged to manually initiate a complete synchronization in the settings, which incorporates as much of your history as possible.

***Something is broken, I demand a fix!*** Please be considerate when leaving a review, this is a free extension that I invest my spare time in. If there is something that does not work then please file an issue on Github where it is easier for me to track.