How to summarize a YouTube video with SageTube

To summarize a YouTube video with SageTube, install the SageTube Chrome extension and click the Summarize button it adds to the video’s action bar — or, if you don’t want to open the video at all, pick Summarize with SageTube from any video card’s three-dot menu on the homepage, search results, or a channel page. Either way you get a structured summary with key points, takeaways, and timestamped chapters (config/faq.php:27). The cost is the transcript: $0.01 per minute for captioned videos, $0.05 per minute when the audio has to be transcribed (config/subscription.php:87–88).

This post covers both entry points in detail. For everything else the extension does — sidebar chat, adding videos to Experts, channel pages — see the complete usage guide.

Where is the Summarize button on the watch page?#

When you open any YouTube video with the extension installed (current version 1.38.6, rag_chrome_extension-master/manifest.json:4), SageTube injects a YouTube-native styled button group into the video’s action bar, alongside Like and Share (src/content/action-button-group.ts:4). It holds three actions: Summarize, Transcribe, and Chat (src/content/action-button-group.ts:21–41).

Click Summarize and the button switches to Summarizing… while the extension sends the request to SageTube’s summarize-video endpoint (src/content/api-client.ts:707). Two details about what happens next:

• When the summary is ready, it opens inline, directly below the button — you read it on the watch page without switching tabs (src/content/features/summarize.ts:49–51).
• If you click again while it’s still processing, the SageTube sidebar opens so you can watch progress there (src/content/features/summarize.ts:43–45). The sidebar is also always available via Ctrl+Shift+G (rag_chrome_extension-master/manifest.json:71–74).

Summaries are cached. Once a video shows Summarize ✓, clicking the button simply toggles the saved summary open and closed instead of paying to generate it again (src/content/features/summarize.ts:23–31). A regenerate action inside the open panel forces a fresh summary when you actually want one (src/content/features/summarize.ts:113–118).

How do I summarize a video without opening it?#

Use YouTube’s own three-dot menu. On the homepage, in search results, and on channel pages, the extension adds two branded items — Summarize with SageTube and Transcribe with SageTube — to the native popup menu on every video card (src/content/context-menu-injector.ts:2–10, 222–223).

Pick Summarize with SageTube and the summary is generated in the background: you get a toast notification when it’s ready, and the sidebar opens on that video’s summary — the video itself never loads (src/content/features/summarize.ts:78–89). If a summary for that video already exists, you’re told immediately (“Summary already available”) instead of being charged again (src/content/features/summarize.ts:84–85).

The practical payoff is triage. Faced with a page of search results, you can queue summaries for the two or three promising videos straight from their cards, keep scrolling, and read the results in the sidebar — instead of opening each video, watching thirty seconds, and backing out.

How much does summarizing a video cost?#

SageTube charges your wallet for acquiring the transcript, and the rate depends on how the transcript is obtained (config/subscription.php:87–92):

• $0.01 per minute of video when YouTube captions exist — SageTube fetches and uses them (config/subscription.php:88).
• $0.05 per minute when there are no usable captions and SageTube must extract the audio and transcribe it (config/subscription.php:87).

In practice, about 64% of the videos SageTube processes have captions and 36% need audio transcription, which is why our public pricing quotes a blended ~$0.025 per minute rather than the optimistic caption-only rate (config/subscription.php:105–109). A typical 20-minute captioned video costs $0.20 to summarize; the same video without captions costs $1.00.

Every tier can run summaries. The free Starter tier starts with a $5.00 wallet balance (config/subscription.php:64) and allows 10 summaries per day (config/subscription.php:63); Builder allows 100, Creator 1,000, and Enterprise 10,000 per day (config/subscription.php:13,32,50). This isn’t a niche feature, either: as of August 2026, SageTube has generated 744 video summaries and holds 26,420 indexed video transcripts in production.

What happens if the video has no captions?#

Nothing you need to manage — the fallback is automatic. The extension reads YouTube’s caption data in the page when it’s available and sends it along with the summarize request as a fast path (src/content/api-client.ts:680–693, src/content/index.ts:32). When no captions exist — private captions, music-only uploads, some non-English content — the backend extracts the audio and transcribes it instead. You get the same structured summary; the differences are the $0.05/minute rate and a longer wait, which is why the extension’s polling allows for the backend needing to fetch and transcribe the video (src/content/api-client.ts:973).

Where does the summary fit in the bigger picture?#

A summary is the fastest way to decide whether a video deserves your attention — but it’s a one-video, one-shot tool. If you find yourself summarizing many videos from the same creator, the better move is adding the whole channel to a SageTube Expert and asking questions across all of it at once, with every answer cited back to the exact video and timestamp. That’s the core product — you can try it at sagetube.ai or browse public Experts other users have shared.