Spaced repetition for the lectures you watch on YouTube.
Cards get spaced review. Videos don't — they get watched once and forgotten. ClipMark puts the moments you saved from a lecture on an expanding schedule and brings them back on the days you were about to lose them.
Video is the one format spaced repetition skipped
The scheduling idea is old and well established: review something just as it starts to fade, and each successful review buys a longer gap before the next one. Anki, SuperMemo, and every review app since is built on it. All of them assume your material is already text on a card. A four-hour lecture isn't, so the usual answer is “make cards from it first” — an hour of transcription for an hour of watching, which is why almost nobody keeps it up.
ClipMark keeps the video as the material. The unit of review is a timestamp with your note attached, so creating one costs a keystroke and reviewing one costs the seconds it takes to remember. The schedule then does the same job it does for cards.
The schedule, stated plainly
- 01
First pass: 1, 3, then 7 days
A newly enrolled moment comes back the next day, then three days later, then a week later — the early gaps where forgetting is steepest.
- 02
Got it — the gap doubles
Each successful recall doubles the next interval, up to a 60-day ceiling. Material you clearly know stops asking for your time.
- 03
Again — back tomorrow
A miss resets the moment to the next day, so the things you keep losing are the things you keep seeing.
- 04
Reviews stay in one queue
Everything due across every video you have saved shows up in one queue on your dashboard, so revision is one session rather than a hunt through your history.
How to revise lectures with this
The workflow that holds up over a term is deliberately unambitious: watch the lecture once, properly, and hit Alt+B at the four or five moments that actually carry the concept — a definition, the step you know you'll misremember, the diagram that finally made it land. Tag them with the subject as you go (any #word in a note becomes a tag). Then let the queue come to you. You are not making a deck; you are marking the parts of the lecture worth being asked about later.
A week in, the queue is the revision plan. Instead of deciding what to go back over — which is where most revision time disappears — you answer what's due and replay only the clips you missed. A three-hour lecture you watched a fortnight ago becomes ten minutes of targeted work rather than a decision about whether to rewatch it.
One tag per subject
Tags are parsed from your notes and colour-coded, so a whole module can be filtered and reviewed as one set.
Groups for a series
Collect the videos in a course into a group and keep a lecture series together instead of scattered across your history.
Reminders when due
Scheduled review reminders are a Pro feature; the review queue itself is on the free tier, capped at 30 reviews a month.
What's free, and what isn't
Free covers unlimited locally stored bookmarks, 25 moments enrolled in the review schedule at any one time, and 30 reviews a month — a real revision habit, not a demo. Pro removes both caps and adds cloud sync across devices, scheduled reminders, and unlimited Anki export. Permanent transcript archiving and deep search inside transcripts are coming soon and not part of Pro today; the pricing page marks them as such.
If you already run Anki
Keep it. ClipMark schedules video moments, which Anki can't hold, and exports them into your existing deck with a link back to the second each card came from — see YouTube to Anki.
Four things we refuse to get wrong.
The player stays clear, the free tier stays honest, the permissions stay narrow, and the thing that makes it stick is built in.
Lives in the side panel, not on top of your video
ClipMark opens in Chrome’s own side panel beside the player. Nothing floats over the video, nothing covers the controls, and YouTube’s keyboard shortcuts keep working — ClipMark only claims Alt+B to save, and [ / ] to step between clips while you’re actively revisiting.
A free tier with the numbers printed on it
Free means unlimited bookmarks stored locally, on-device AI notes, 25 Active Recall cards, 30 reviews a month, and 10 Anki exports a month — no card, no trial clock. Those are the real limits, listed on the pricing page rather than discovered after you install.
Two hosts. That’s the whole permission list
ClipMark asks for youtube.com and clipmark.mithahara.com — its own sync domain — and nothing more. It cannot read your banking tab, your email, or any other site, because it was never granted them. AI notes run on Chrome’s on-device model, so transcripts aren’t shipped anywhere for that.
Your note is the question. The clip is the answer.
Tools that quiz you on a video generate the questions themselves, from the transcript. ClipMark does the opposite: it hides the note you wrote and replays the exact second, so you check your own recall against the source. Every saved moment goes on a schedule — 1, 3, then 7 days, doubling up to 60. That retrieval loop is the product, not a bullet point.
Switching from an extension that stopped getting updates? Read the migration guide.
Keep reading
Revise the lecture, not your whole watch history.
Save the moments that carry the concept, and let the schedule decide when you see them again.
Add ClipMark to Chrome — FreeFree tier needs no card. Works in Chrome, Edge, and Brave.