YouTube Summarizer Chrome Extension

Turn the YouTube lecture you're watching into notes, timestamped chapters, key terms, a full transcript and a quiz — one click, no copying links, no API key. Works on videos that have captions or subtitles.

⬇ Download Extension (free)

You're on a phone. Chrome extensions only install on desktop Chrome, Edge or Brave. Open this page on a computer to add it — or, on this phone right now, record or upload a lecture instead. That path works everywhere and needs nothing installed.

How to install (takes 1 minute)

Download and unzip

Click the download button above and unzip the file anywhere on your computer.

Open Chrome Extensions

In Chrome, go to chrome://extensions and turn on Developer mode (top-right toggle). Then click Load unpacked.

Enable Developer mode and click Load unpacked

Select the extension folder

In the file picker, navigate to where you unzipped the file and select the extension folder.

Go to any YouTube video and click the icon

The VideoNoteGPT icon will appear in your Chrome toolbar. Click it while watching any YouTube video.

Click Summarize and wait

The popup shows the video's title. Click Summarize this video — the extension reads the video's captions in your browser and sends the text to VideoNoteGPT. Your notes open in a new tab when they're ready.

Why an extension, and not just a box you paste a link into

This is the question we get most, and the honest answer is not a design preference. YouTube refuses requests that arrive from datacentre servers. Every tool that runs on rented infrastructure — ours included — sits behind exactly the kind of IP address YouTube declines to serve. So a pasted YouTube link cannot reach the video's audio from our side, no matter how the box on the page is worded.

Plenty of sites promise otherwise. If you have tried one and watched it spin and fail, that is why: we tested it on our own production server and wrote up what came back.

The extension takes the other route. It runs inside the browser session you are already watching in, and it reads the caption track the video already carries — the same request your own player makes when you turn subtitles on. Nothing is downloaded, nothing is re-recorded, and no request is made from our machines to YouTube at all. That is the whole trick, and it is why the extension works where the paste box cannot.

It is also fast. Because the captions are already text, there is no transcription step to wait through: the summary starts generating the moment you click.

What one click actually gives you

Most YouTube summary extensions put a paragraph or a bulleted TL;DR in the sidebar and stop there. That is useful for deciding whether a video is worth watching. It is not much use the night before an exam.

Clicking the icon produces the same full result the website does, opened in its own tab:

Timestamped chapters — the video split into named sections, each linked to the moment it starts.
Up to 20 key points, each with the timestamp where it was said.
Key terms and definitions, tagged by difficulty.
A full, cleaned transcript with punctuation and paragraph breaks — searchable with Ctrl+F, which beats scrubbing the timeline.
An AI quiz — 5 to 20 multiple-choice questions, three difficulty levels, graded with explanations.
An audio recap — a 3, 5 or 10 minute spoken summary you can listen to on the walk home. It never uses up a lecture.
Exports — Markdown, PDF, Obsidian, SRT/VTT subtitles, and Anki .apkg flashcards built from the key terms.
A share link for the finished notes, which classmates can open without an account.

How it compares to sidebar summary extensions

The Chrome Web Store has a crowded shelf of YouTube summarizers — Eightify, NoteGPT, BibiGPT, Clarify AI, "YouTube Summary with ChatGPT & Claude" and others. They are good at what they do, and what they do is different from this. Checked August 2026:

	Typical sidebar summarizer	VideoNoteGPT extension
Output	TL;DR paragraph or bullets, in the page	Chapters, key points, terms, transcript, quiz, flashcards
Where it lands	Beside the video — quick to skim, gone when you close the tab	A saved page you can revisit, share and export
Speed to first words	Usually faster — less is being produced	Slower; a full study set takes longer to write
Setup	Several want an account, an API key or a linked ChatGPT session	Install and click — no account, no key
Revision tools	Rare; a few offer mind maps	Graded quiz and Anki `.apkg` export
Price	Free tier common; the well-known ones charge for volume	Free to start; Pro is $6.99/mo

Pick the other kind if you mostly want to triage a watch-later list — a sidebar TL;DR is the right tool and it is quicker. Pick this one if the video is coursework and you are going to be tested on it.

One click while you're watching

No copying URLs, no downloading files. Click the toolbar icon and keep watching.

Reads captions in your browser

The request comes from you, not from our server — which is why it works where pasting a link doesn't.

Any language, auto-detected

Picks the video's own caption track, in English, Bengali, Arabic, Spanish and 90+ more.

Free to use

No account required for the extension itself. Uses one of your daily lectures.

What it can and can't do

✓

Works on videos that have captions

Including YouTube's automatic captions, which most lectures and talks have. The extension reads that caption track — it does not re-transcribe the audio, so it's fast. Unlisted videos your own account can see are covered too.

Won't work if captions are turned off

Some uploaders disable captions entirely, and private or age-restricted videos can't be read either. For those, record or download the lecture and upload the file to VideoNoteGPT — Whisper will transcribe the audio itself.

Chrome and Chromium browsers only

Built on Manifest V3, so Chrome, Edge, Brave, Opera and Arc all work. There is no Firefox or Safari build. On a phone, record or upload from the website instead.

Permissions, and what happens to your data

An extension that can read a page you are logged into deserves a straight answer about what it touches. This one asks for three permissions and no more:

activeTab — read the video you are on, only at the moment you click the icon.
storage — remember your VideoNoteGPT session so the notes land in your library rather than an anonymous one.
scripting — run the small script that pulls the caption track out of the page.

It runs on youtube.com/watch pages and on videonotegpt.com, and on no other site. It does not read your browsing history, your other tabs, your cookies for other domains, or anything you do outside a YouTube video page. There is no third-party analytics inside the extension.

What leaves your browser is the caption text of the video you asked about. On our side it is summarized and the source material is deleted within 24 hours; it is never used to train models and never sold. The full terms are in the privacy policy, which covers the extension specifically.

Frequently asked questions

Why do I need an extension to summarize a YouTube video?

YouTube blocks requests that come from datacentre servers, so no web tool can reach a YouTube video's audio from its own machines with a pasted link. The extension runs inside your own browser session instead and reads the video's caption track — the same request your player already makes — which is why it works where a pasted link does not.

Is the Chrome extension free?

Yes. The extension itself costs nothing and needs no account to install. Summarizing uses one of your free lectures, and new visitors get 3 a day — any length. There is no API key to supply and no OpenAI or Claude subscription to connect. See the full pricing.

What does the extension actually produce?

The same result the website produces: timestamped chapters, up to 20 key points, a key-terms list with definitions, a full cleaned transcript, an AI quiz you can take and have graded, a spoken audio recap, and exports to Markdown, PDF, Obsidian, Anki .apkg and SRT or VTT subtitles. It is a study set, not a paragraph-long summary in the sidebar.

Which videos does it work on?

Any YouTube video that has a caption track, including YouTube's automatic captions, which most lectures, talks and tutorials have. That covers unlisted videos your own account can see. It cannot read a video whose uploader disabled captions entirely, nor private or age-restricted videos — for those, upload your own recording and Whisper will transcribe the audio.

What permissions does it ask for, and what does it do with them?

Three: activeTab, storage and scripting. It runs on youtube.com/watch pages and on videonotegpt.com, and nowhere else. It does not read your browsing history, your other tabs, or any other site. Captions are sent to VideoNoteGPT to be summarized and the source material is deleted within 24 hours.

Does it work in languages other than English?

Yes. It picks up whatever caption track the video carries, and VideoNoteGPT handles 100+ languages including Bengali, Arabic, Spanish, Hindi and Mandarin. The summary is written in English by default and can be translated afterwards.