How to summarize a YouTube video without downloading it
Open a supported video, click Silestis, and turn it into a summary plus timestamped answers without manually downloading or copying a transcript.
The fastest way: one click on the page
You're already watching the video, so you do not need to download it manually or paste a link. For supported pages, the Silestis extension for Safari (Chrome extension coming next) starts transcription from the page and returns a summary, key points, and a transcript. Timestamps depend on the selected mode; processing time depends on source, duration, format, and current load.
No download, no copy-paste
Downloading a YouTube video is slow, clutters your disk, and is often against the platform's terms. Silestis never asks you to download: it works with the audio on the page you already have access to. Source media is deleted after transcription by default, and Silestis does not use your content to train its own models. Prefer not to install the extension? You can also paste the link into the web app.
Ask follow-up questions
A summary is the start. Ask "what were the three main arguments?" or "what did they say about pricing?" When the selected mode provides timestamps, the answer can include clickable [mm:ss] references so you can verify it in the video.
See it for YouTube videos, or how Silestis compares to Google NotebookLM.
FAQ
Do I need to download the YouTube video first?
No. Silestis works with the audio on the page you're already watching — no download, no copy-paste. Source media is deleted after transcription by default; optional playback copies are retained only when you choose to keep them.
What if the video has no captions?
If usable captions exist, Silestis can use them for a fast result. Otherwise it can transcribe supported audio with your selected AI mode; processing time varies by source, duration, format, and current load.
Is it free?
Yes, there's a free tier so you can summarize a few videos before choosing a plan. No credit card required.
Start from the supported lecture page you already use.
Open the video and click Silestis to start a transcript, summary, and notes workflow on the page. Timestamp-capable modes can also return cited answers, including when no source transcript exists.
Get the Safari Extension