Drum Groove Tool
Record a take
Play along to a click. The tool finds every hit and shows whether you rush or drag, how consistent you are, which drum is early or late, and how much you swing. Everything runs in your browser; your recordings never leave this device.
Analyzing your take…
Takes are saved in this browser only. Clearing site data removes them; download any recording you want to keep.
Why teach it your kit?
Out of the box, the tool guesses which drum was hit from fixed frequency ranges. That works on clean audio but mixes up kick and snare on phone and laptop mics. Teaching it fixes that: you play a few hits on each drum, and it learns what your drums sound like on this mic in this room. A profile called default is used automatically.
Learn a new kit profile
Measure your audio delay
Every computer takes a moment to play a sound and hear it back. Measure that delay once, so “ahead of / behind the click” is accurate. Take headphones off and turn the volume up: the tool plays 12 clicks through your speakers and listens with the mic. Stay quiet while it runs.
When you record, wear wired headphones for the click, so the mic doesn't pick it up. Bluetooth headphones add a delay this measurement can't see.
Coaching from Claude (optional)
After a take, Claude, Anthropic's AI model, can read your numbers like a drum teacher: what's working, timing fixes, exercises, and groove and fill ideas built from how you played. It uses your own Anthropic API key, at roughly 10–25 cents per take. Everything else on this page is free.
Getting a key, and keeping it safe
- Sign in at console.anthropic.com (separate from a Claude.ai subscription).
- Add prepaid credit under Settings → Billing. $5 covers a lot of takes, and nothing renews automatically.
- Create a key under Settings → API Keys and paste it above.
Your key goes from this browser straight to Anthropic (api.anthropic.com) and nowhere else. Unless you tick “remember”, it's forgotten when you close the tab. Anyone with the key can spend your credit, so don't use this on a shared computer, and if a key is ever exposed, delete it in the Console and make a new one.
What's sent: only the timing numbers and your groove written as a grid (e.g. “19 ms ahead of the click, snare on 2 and 4”), plus the note above. Your recording never leaves this device.
About the AI suggestions
Improvising is about your own ideas, reacting in the moment. Nobody starts from nothing, though: drummers have always learned vocabulary from teachers, records and each other, then made it their own. The suggestions are that kind of vocabulary, built from your groove and tendencies. Every idea comes with ways to change it, and the “Your turn” challenges give you a constraint and leave the playing to you. The research notes in each report come from a hand-checked list of studies, never from the AI.