Update: My bookmarklet has been broken by Google, but the script it was based on has been fixed and has added support for 720p HD downloading. Use that instead.
In addition to expanding their player to 960px wide for all videos, YouTube received a more quiet upgrade today. In addition to normal quality and high quality, they have now added 720p HD video. Few HD YouTube videos exist at the moment, but for those that do you can simply append &fmt=22 to the end of the URL. Interestingly, I seem to be the first to have figured out how to actually download (rather than stream) these new 720p HD videos directly from YouTube.
Simply drag this link to your bookmarks bar: DL YouTube HD
This is what is known as a bookmarklet, a JavaScript bookmark able to act on the current page. To use it, find a YouTube video that’s available in 720p (example). Click on the bookmarklet, and at the bottom of the gray info box on the right a link labled “Download as 720p HD MP4″ will appear. Right-click and save, and the download will begin.
Credits: My bookmarklet is a modification of googlesystem.blogspot.com’s bookmarklet for downloading high quality (but not HD) YouTube videos, which I found via robotdestroy on MacOSXHints.
Update: After seeing my bookmarklet, Nathan Hammond took it even further by making his own bookmarklet that automatically starts the download. Very nice!

[...] wurde ich im Blog von Paul Tow. Dort findet man ein Bookmarklet, das ein Javascript enthält, das direkt auf der entsprechenden [...]
THANK YOU!!!!
Works just fine!
Thanks man, this is the most simple way to do it! U just made my day.
Hey great….can I download from dailymotion this way as well?
[...] http://www.paultow.com/2008/11/25/how-to-download-youtube-videos-in-720p-hd/ [...]
Nat, I apologies for taking so long to respond. I’ve been a little busy, but wanted to give you some kind of response.
A quick Google search turned up a Greasemonkey script which adds a link to download the Dailymotion video as an mp4. However, that’s not a bookmarklet and I’m guessing it doesn’t download in HD. Hopefully that will help you or offer clues to someone else.
Note: I’ve not tested the Greasemonkey script.
I think there is an easier way to download videos from youtube. Just paste the URL from the video in the http://www.keephd.com website and click in download.
or (even easier) when watching a video in youtube website you want to download, just change “youtube” to “keephd” in the URL from the video you are watching.
this is so easy, and perfect. Thanks. is a big workk
Paul, I noticed a few weeks ago the script stopped working (around mid October). I thought my bookmark was messed up, but I think something at YouTube has changed. Any thoughts? Will you have an update?
Same comment as Darryl – the very helpful script you provided no longer works. Any chance of an update?
Indeed, they do seem to have changed things. Buzz Out Loud recently reported that YouTube will be getting 1080p, so perhaps that’s why. I’ll try to figure out a fix if I can find the time. I have a guess at the fix.
As I’ve now noted at the top of the post, the bookmarklet that my bookmarklet was based on has been fixed to work with the changes Google made, and 720p HD support was added to it. You should now use that bookmarklet instead.
http://googlesystem.blogspot.com/2008/04/download-youtube-videos-as-mp4-files.html
doest work
Logan, read the update at the top of the post.
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