Tool
Polyrhythm metronome
Choose two whole numbers from 2 to 8. The higher click plays the first number. The lower click plays the second. One cycle lasts as long as the second number of beats at the session tempo. 3 against 2 means three high clicks in the same span as two low clicks.
Tempo comes from the session bar. Set BPM on the metronome if you need another speed.
How the two pulses line up
The cycle length is (60 / BPM) × the second number. That span is split into equal steps for each side. Both sides begin together. This page uses its own clicks so it does not fight the shared metronome. Stop the session click if the two layers feel crowded.
Numbers outside 2 through 8 are rejected. The tool will not start a 1:1 click here; use the metronome for a single pulse.
Worked examples
Two beats last one second. Three high clicks fill that second. Can you tap the high side while your foot keeps the low side?
Four against three shares a downbeat, then the inner attacks miss each other until the next cycle. Do you hear the return?
Five against four is denser. Start slower on the session metronome, then open this page and start the pair.
Questions
Why does this click ignore the session Start click button?
Two schedulers in one tab will drift against each other. This page owns its pair. The session bar still stores BPM for the cycle length.
Is 4 : 4 useful?
Both sides land together, so you hear one reinforced pulse. It is a check that the two voices share a downbeat, not a new meter.
Does 6/8 change the cycle?
No. The cycle uses session BPM as a quarter-note pulse, the same way the delay table does.