Polyrhythm Generator
Enter any two beat counts and a tempo to see exactly where the hits land — as a shared step grid and as millisecond timings you can practice against.
3-against-4 polyrhythm
Top row: 3 evenly-spaced hits (highlighted at steps 0, 4, 8). Bottom row: 4 evenly-spaced hits (highlighted at steps 0, 3, 6, 9), both on a shared 12-step grid.
| Hit # | 3-side (ms) |
|---|---|
| 1 | 0 |
| 2 | 333.33 |
| 3 | 666.67 |
| Hit # | 4-side (ms) |
|---|---|
| 1 | 0 |
| 2 | 250 |
| 3 | 500 |
| 4 | 750 |
Reading the grid
The two rows above show one full cycle of the polyrhythm. Each row is divided into the same number of steps — the least common multiple of your two beat counts — so the two rhythms can be compared position by position. A highlighted square marks a hit; where both rows highlight the same step, both rhythms land together.
The millisecond tables underneath give the actual time of each hit within a single beat at your chosen tempo, which is the number you actually need if you are programming a click track, a drum machine, or checking your own timing against a reference.
Frequently Asked Questions
What is a polyrhythm?
A polyrhythm is two (or more) rhythms with a different number of evenly-spaced beats played across the same span of time — for example, one hand playing 3 evenly-spaced hits while the other plays 4, both finishing together. The classic 3-against-4 is the most common starting point for learning the feel.
How is the shared grid calculated?
The smallest grid where both rhythms land on whole-number positions is the least common multiple (LCM) of the two beat counts. For 3-against-4, LCM(3, 4) = 12, so the combined pattern repeats every 12 subdivisions: the 3-side lands on steps 0, 4, and 8, and the 4-side lands on steps 0, 3, 6, and 9 — they only coincide at step 0.
How do I practice a polyrhythm from the numbers?
Start slow enough that you can consciously place each hit from the millisecond timing table, then gradually speed up until the pattern becomes physical rather than counted. Many players find it easier to say a word with the right syllable count out loud — 'pass the but-ter' for 3 against 'wa-ter-mel-on' for 4 — while tapping both hands.
Educational tool only. Timings are exact mathematical subdivisions of the beat — real playing feel comes from practice, not the millisecond figure alone.