Ghost Note, a free drum play along

1. Bring a track

Drop an audio file here, or choose one below. MP3, WAV, M4A, OGG, FLAC, whatever your browser plays.

Ready when you are.

2. The chart

Nothing loaded yet.

0:00 / 0:00 Bar 1, beat 1 Space plays and stops.

No loop set. Drag either handle on the bar above to mark a section.

Speed 100% Slow it down to learn a part. The pitch is held steady, so it stays in the right key.

Time signature 4/4

Counted in four unless the track clearly says otherwise. Change it here if the bar lines look wrong.

Quieten the center off Pulls down whatever sits dead center, usually the kick, snare and lead vocal, so you get to be the drummer. Rough, and it needs a stereo file.

Count in Counted in bars, so a waltz gets three and not four.

Click A steady click on the beat the app found.

Chart zoom 100%

Stretch the chart out when fast hits are packed together. Pinch the chart on a phone, or hold Control and scroll.

3. Play it

Score: 0
Combo: 0
Accuracy: 0%
Timing: no data yet

Perfect 0, great 0, good 0, missed 0

Ends the run, shows how it went and saves the result.

How that run went

No run yet.

Accuracy: 0%
Best combo: 0
Timing: no data
Consistency: no data

Where your hits landed

Everything to the left of center is early, everything to the right is late. A tall middle bar is the goal, and a wide flat spread means the timing is inconsistent rather than simply offset.

Lane by lane

Accuracy, timing and misses for each drum
Drum	Played	Accuracy	Timing	Missed

Your charts and your history

Saved in this browser on this device. Nothing is uploaded, which also means clearing your browser data clears these.

Name for this chart

Your edits are kept automatically as you work. Saving under a name is how you keep more than one.

Saved charts

Nothing saved yet.

Recent runs

No runs yet.

Export and save to a file

The MIDI lands on channel 10 with General MIDI drum notes, so any DAW will read it. A chart file is the one to send someone else, since your library only lives in this browser.

Kit, keys and latency

Electronic kit

Not connected. The keyboard and the pads above work on their own, you never need hardware.

Latency calibration 0 ms

Play eight clicks and tap along on any pad or key. Your output delay gets measured once and subtracted from every judgment after that, so the app stops blaming you for the browser.

Detection sensitivity normal Higher finds quieter hits and more mistakes. Re analyze after changing it.

What this actually does, and what it does not

It finds drum hits with spectral flux onset detection, then sorts them into kick, snare and hi hat by where their energy sits in the spectrum. That is classic signal processing, not machine learning, so there is no model to download and the analysis takes a couple of seconds.
Toms and cymbals are not detected as such. They land in the nearest of the three lanes and usually come through with low confidence. Notes the detector was unsure about are drawn with a dashed outline, and the editor is there so you can fix them.
It does not separate the drums from the rest of the mix. The center cut in the transport is a rough stand in. Real separation means tens of megabytes of model weights, which is a fair upgrade one day but not something to make you wait for now.
Your file never leaves this device. There is no account, no upload, no analytics. Your charts and your run history are kept in this browser and go no further.