StreamgrabWhy a video will not download, and what no extension can do
Updated
Usually one of five things is going on: the video is protected by DRM, it is on YouTube, the player hides it behind a blob: address, it is a live stream, or the extension has not seen it load yet. The first two are limits no extension can or may get around. The last three can often be fixed. Here is how to tell which one you have.
1. It is protected by DRM
Paid streaming services encrypt their video with a system such as Widevine, PlayReady or FairPlay. The key stays inside the browser's secure module, and the pieces on the server are unreadable without it. An extension can fetch the pieces, but they are scrambled, and getting around the encryption is against the law in many countries. No extension can do this, and Streamgrab refuses it with "This stream is protected by DRM and cannot be downloaded." Plain AES-128 encryption is a different case: its key is a link in the playlist, and Streamgrab handles it.
2. It is on YouTube
Streamgrab does not download from YouTube, on purpose. YouTube's terms do not allow downloading except through the features YouTube provides. If the video is yours, the YouTube Studio page for your channel lets you download your own uploads. For offline viewing of other people's videos, use the offline feature in the YouTube app.
3. The address starts with blob:
A blob: address in the player is a local handle to data the page built in memory. It is not on any server, so there is nothing to download from it. Behind it, the page usually fetched an m3u8 playlist, an mpd manifest, or an MP4 from the network. Those are what a downloader should find, and Streamgrab lists the ones it recognises: MP4 and WebM files over 100 KB, m3u8 playlists and mpd manifests. If the page uses another method to fetch its video, Streamgrab will not see it, and the popup says: "No video found on this page yet. Start playing the video and it will appear here."
4. It is a live stream
A live DASH stream has no end, so Streamgrab cannot save it as a file and says so. A live HLS stream can be recorded on Pro: press Record and it follows the playlist until you press Stop or the stream ends. If a stream is later published as a recording, that recording can be downloaded on any plan.
5. The extension has not seen it
- Press play. Streamgrab only lists what the page has requested. Start the video and watch the toolbar icon.
- Reload the page if you installed the extension after it loaded.
- Wait a moment. Some players request the playlist only after an ad or a click.
- Try again later. If the server refuses the request, the address may have expired. Reload and start again.
Limits that are not DRM
- Size: limited by free disk space, since the file is built in the browser's private storage.
- Several parts: a DASH stream split into parts, such as one with an ad break, cannot be joined.
- Free plan: HLS and DASH streams up to 720p, one at a time. Direct MP4 and WebM files are not limited. Pro costs €29 for life or €15 for 12 months.
What is left
If the video is a plain MP4, an unprotected HLS playlist or a DASH manifest, Streamgrab or yt-dlp will do it, and the guides for m3u8 and mpd show how. If it is DRM or YouTube, the answer is to use the service's own offline feature, or to ask the owner for a file. Streamgrab runs in Chrome, Microsoft Edge and Firefox on desktop. Download only what you have the right to keep.
Questions
- Why can I not download a Netflix or Disney+ video?
- Those services protect their video with DRM. The pieces are encrypted and the key stays inside the browser. Streamgrab refuses such streams, and no extension can lawfully remove that protection.
- Can Streamgrab download YouTube videos?
- No. Streamgrab refuses YouTube addresses on purpose. The YouTube app has its own offline feature, and creators can download their own uploads from YouTube Studio.
- What is a blob: video address?
- It is a local handle to data the page built in memory. The real video came from the network, often as an m3u8 playlist, an mpd manifest or an MP4 file, and a downloader looks for those.
- The popup says no video was found. What now?
- Start playing the video, and reload the page if you installed the extension after it loaded. Streamgrab lists only what the page requests while you watch.
Save a stream as a file
Streamgrab is free to start, with no account and no watermark. Direct MP4 and WebM files are never limited.
Streamgrab runs in Chrome, Microsoft Edge and Firefox on desktop. Download only what you have the right to keep. Streamgrab is an independent product.