Note Duration Calculator (BPM to ms)

Note duration from BPM: formula and example

Every note value runs for duration_ms = 60000 / BPM · relative_value, with the quarter note set to a relative value of 1. So at 120 BPM you get a quarter note of 500 ms, an eighth at 250 ms, a sixteenth at 125 ms, a half note at 1000 ms and a whole note at 2000 ms. For the quarter note on its own the math collapses to 60000 / BPM.

Context and applications

Producers reach for these numbers to lock delay and reverb to the grid in DAWs like Ableton Live, FL Studio and Logic Pro. A quarter-note delay at 120 BPM is just the plugin set to 500 ms, which drops each echo right on the next beat. Side-chain compression releases often get dialed in to an eighth or a sixteenth. The same math shows up when DJs beatmatch a crossfade, when drummers program a metronome by subdivision, and when composers work out how long a phrase will run.

FAQ

What is a dotted note? The dot tacks on half of the original value, so a dotted quarter at 120 BPM works out to 500 + 250 = 750 ms. You hear it a lot in U2-style delays.

What about triplets? A quarter-note triplet packs three notes into the space of two. Divide the quarter duration by 1.5 and you land at 333 ms at 120 BPM.

Does the formula change with time signature? It doesn't. By convention BPM points at the quarter note in 4/4, and signatures like 6/8 or 3/4 still run on the same per-beat math.

How does this relate to Hz? The note duration is just the period, so the matching rhythm frequency in Hz comes out as BPM / 60. That makes 120 BPM equal to 2 Hz.