BPM (Beats per Minute)

BPM stands for beats per minute. It is the number a metronome, a drum machine or a music app uses to describe tempo: set 60 BPM and you hear one click every second; set 120 and the clicks come twice as fast.

In printed music the same number appears as a metronome mark: ♩ = 120 means 120 quarter-note beats per minute. The older abbreviation M.M. (Maelzel's Metronome) in front of the mark means the same thing.

▶60 BPM0:09▶120 BPM0:06

The math

One minute is 60 seconds, so:

• seconds per beat = 60 ÷ BPM
• milliseconds per beat = 60,000 ÷ BPM

At 120 BPM a quarter-note beat lasts 500 milliseconds, an eighth note 250 and a sixteenth note 125. At 90 BPM a beat lasts about 667 milliseconds. Producers use exactly this arithmetic to set delay and reverb times that line up with a song; the Tempo Math worksheet walks through it step by step.

Which note is the beat?

BPM counts beats, so it matters which note value is the beat. In 2/4, 3/4 and 4/4 it is usually the quarter note. In 6/8 the music is felt in two beats of a dotted quarter, so ♩. = 60 means 60 dotted quarters per minute, which is 180 eighth notes. In cut time the beat is the half note. A metronome mark shows its beat unit; a bare BPM figure on a recording or in a DAW usually counts quarter notes.

BPM in recorded and electronic music

In a DAW, the tempo setting is a BPM number, and the grid, loops, the click track and tempo-synced effects all follow it. Some styles are strongly associated with tempo ranges; house music, for example, often sits somewhere around 120 to 130 BPM. But a ballad and a dance track can share a BPM and still feel completely different, because the feel also depends on how the beat is subdivided and where the accents fall.

To connect BPM numbers with the Italian tempo words, see the speedometer in Tempo & the Metronome, then match six metronome marks to their words in Dynamics & Tempo Ladders.