Metronome Subdivision Calculator
Calculate the millisecond interval for any rhythmic subdivision of a given BPM. Covers quarter, eighth, triplet, sixteenth, and 32nd note subdivisions.
How to use this tool
- Enter bpm and subdivision in the fields above.
- Results update instantly as you type — or click Calculate.
- Read your subdivision and the full breakdown beneath it.
Find the exact millisecond timing for any beat subdivision at your tempo.
⚠ This tool provides general estimates for education only and is not financial, tax or legal advice. Figures may not reflect your situation — verify with a qualified professional.
Formula
Beat duration (ms) = 60 000 ÷ BPM
Subdivision duration (ms) = beat duration ÷ subdivision factor
How it works
This calculator converts a tempo in BPM to the duration of a single beat and then divides by the subdivision factor to find the interval for smaller rhythmic units. A subdivision of 1 gives the quarter-note beat; 2 gives eighth notes; 3 gives quarter-note triplets; 4 gives sixteenth notes, and so on.
Results are exact for steady-tempo playback and are useful for programming delay times, sequencer grid divisions, or drum machine step lengths. The calculation assumes all beats are equal in duration (no swing or groove quantisation).
Worked example
- BPM = 120, subdivision = 1 (quarter-note beat).
- Beat duration = 60 000 / 120 = 500 ms.
- Subdivision duration = 500 / 1 = 500 ms.
Beat duration: 500 ms | Subdivision: 500 ms
Common mistakes to avoid
- Confusing triplet subdivisions with straight subdivisions; a quarter-note triplet is beat_ms / 1.5, not beat_ms / 3 (which gives an eighth-note triplet).
- Setting a delay or sampler step to the subdivision interval without accounting for note-off duration, causing overlapping or clipped notes.
- Entering the half-time BPM feel instead of the actual song BPM, halving all subdivision times incorrectly.
Key terms
- BPM (beats per minute)
- The number of quarter-note beats in one minute; the standard measure of musical tempo.
- Subdivision
- The division of a beat into smaller equal parts. An eighth note subdivides the beat by 2; a sixteenth note by 4; a triplet by 3.
- Delay time
- In audio production, the interval between the original sound and its echo. Tempo-synced delay times are derived from beat or subdivision durations.
- Quantisation
- The snapping of recorded notes to the nearest rhythmic grid position. The grid spacing is a subdivision of the beat.
- Swing (groove)
- A deliberate timing deviation where alternating subdivisions are played slightly late, creating a lilting feel. This calculator assumes straight (unswung) timing.
Frequently asked questions
- What is a sixteenth note at 120 BPM?
- At 120 BPM each beat is 500 ms; a sixteenth note (4 per beat) is 125 ms.
- How do I calculate triplet timing?
- Divide the beat duration by 3. At 120 BPM that is 500 / 3 = 166.67 ms per triplet.