Loop YouTube videos to learn drums

Paste a YouTube link, loop the bars you're stuck on, slow them down, and write the drum part on the staff while the video plays. The kit lights up the drum to hit.

How to learn a song with it

Paste a link. Any YouTube video that allows embedding: a song, a drum cover, a live version or a lesson.
Line up the bars. Tap the tempo, then press Set the 1 on a downbeat. Nudge by 10 ms until the notes sit on the music.
Loop and slow down. Loop one, two, four or eight bars and drop the speed to 0.5x or 0.75x. The effective BPM shows as you go.
Write the part. Start from a basic rock beat or an empty chart, click the staff to add notes, and copy a bar across the verse.
Play along and share. Turn on the guide drums to hear your part with the record, then copy the link to come back to it.

New to the kit? Start with the Billie Jean drum play-along lesson: the beat first, then fills, then the record.

Questions

Does it download the video?: No. The video plays in YouTube's own embedded player, straight from YouTube. Nothing is downloaded, recorded or copied; the drum part you write is the only thing saved, in your browser and in your link.
Why won't a video play?: Some owners switch off embedding, so their video only plays on youtube.com. The tool says so when it happens; search for another upload of the same song (a lyric video, a live version or an audio upload) and paste that instead.
How do I find the tempo?: Press Tap tempo (or the T key) in time with the beat four to eight times. A stray tap is ignored, and tapping a slowed-down video still gives the song's real tempo.
The notes drift away from the music later in the song. Why?: Most records hold a steady tempo, but a live band speeds up and slows down. Loop the section you're learning and press Set the 1 at its start, or adjust the BPM by a tenth at a time.
Does it work on a phone?: Yes. The video sits on top, the two bars you're on and the kit below it, and the controls under those.