BPM to Hz Calculator

What Beats per Minute and Hertz Each Count

Tempo and frequency are both rates, but they count different events. Beats per minute counts how many musical beats pass in one minute. Hertz counts how many complete cycles pass in one second. Treat one beat as one cycle, and the two numbers describe the same pulse on different time scales.

The hertz is a derived SI unit equal to one reciprocal second, written s^-1. The BIPM SI Brochure defines it that way, and the NIST SI units page lists the same definition. The only constant the conversion needs is the 60 seconds inside a minute.

At 120 BPM a beat lands twice every second, so the tempo is 2 Hz. A 4/4 bar holds four beats, which makes the bar 2 seconds long and gives a bar rate of 0.5 Hz. A 60 BPM tempo is 1 Hz, and an 80 BPM tempo is 1.3333 Hz.

Keep the meaning of hertz in view. A tempo of 2 Hz is not a 2 Hz audio tone. Sound at 2 Hz sits below the range a person can hear, which starts near 20 Hz. Tempo hertz measures musical time, while pitch hertz measures pressure waves reaching the ear.

The Conversion Formula and Its Inverse

The forward formula is short: Hz = BPM / 60. Divide the tempo by 60 because a minute holds 60 seconds, and the result is beats per second, which is the same count as cycles per second for a steady pulse.

The inverse runs the same arithmetic backward: BPM = Hz x 60. A 1 Hz pulse is 60 BPM, 1.5 Hz is 90 BPM, and 2.5 Hz is 150 BPM. Neither direction needs a lookup table, and a round trip returns the starting value with no drift.

Work one case by hand. A track at 132 BPM gives 132 / 60 = 2.2 Hz. Multiply 2.2 by 60 and the tempo comes back as 132 BPM. Try 174 BPM and the result is 174 / 60 = 2.9 Hz, the tempo used by many drum and bass tracks.

The 60 is exact, not rounded. A minute is defined as 60 seconds, so the divisor carries no uncertainty. Everything else follows from the tempo you enter, and a tempo with decimals works the same way: 127.5 BPM is 2.125 Hz. A metronome marking of 208 BPM, common in fast punk and drum and bass, converts to 208 / 60 = 3.4667 Hz.

A Quick Table of Common Tempos

The table converts tempos that appear in metronome markings, playlists, and DAW projects. The hertz column is the tempo divided by 60, the seconds column is 60 divided by the tempo, and the millisecond column is 60000 divided by the tempo.

Two rows are worth memorizing. At 60 BPM one beat is exactly 1 second, the easiest anchor in the whole table. At 120 BPM the beat is half a second, so delay times and envelope settings written in milliseconds line up with the grid without a calculator.

Notice how slowly the hertz column moves. Going from 60 to 120 BPM doubles the rate from 1 Hz to 2 Hz, while going from 120 to 180 BPM only adds 1 Hz. Human hearing spans roughly 20 Hz to 20,000 Hz, so every musical tempo sits in the bottom sliver of that range.

Beat Length in Seconds and Milliseconds

Beat length is the reciprocal of tempo, scaled to the unit you need. In seconds, T = 60 / BPM. In milliseconds, T = 60000 / BPM. The second form is the one to use for delay plugins, gate times, and envelope release settings, because those controls are labeled in milliseconds.

At 140 BPM, 60 / 140 = 0.4286 seconds, and 60000 / 140 = 428.57 milliseconds. At 90 BPM, 60 / 90 = 0.6667 seconds, and 60000 / 90 = 666.67 milliseconds. Multiply either answer by the tempo and the product returns to 60 seconds per minute.

Subdivisions follow by dividing the beat. An eighth note is half a beat, a sixteenth is a quarter, and an eighth-note triplet is a third. At 120 BPM the quarter note is 500 ms, the eighth note is 250 ms, the sixteenth note is 125 ms, and the eighth-note triplet is 166.67 ms. A dotted eighth is 1.5 times an eighth, so 250 x 1.5 = 375 ms.

The hertz column for note values is the tempo hertz multiplied by the fraction of the beat. A sixteenth note at 120 BPM repeats 8 times per second, so it sits at 8 Hz. That is still audio-rate only in the loosest sense: 8 Hz is a flutter, not a tone.

Running the Formula Backward: Hertz to BPM

Hertz to BPM is a multiplication: BPM = Hz x 60. The table covers rates that appear on LFO rate knobs, tremolo controls, and pulse generators, plus the length of one full cycle in seconds.

A 0.25 Hz LFO completes one cycle every 4 seconds. At 60 BPM a bar of 4/4 lasts 4 seconds, so 0.25 Hz matches one bar. At 120 BPM that same bar lasts 2 seconds, so the LFO needs 0.5 Hz to stay on the bar. This is why a synced LFO changes hertz when the tempo changes.

The 0.1 Hz row is a slow sweep: 6 BPM, one cycle every 10 seconds. The 5 Hz row runs at 300 BPM, which is outside normal musical tempo but common in sound design. A 0.75 Hz pulse lands at 45 BPM, and 1.25 Hz lands at 75 BPM.

Where the Conversion Shows Up

Delay time is the most common use. A quarter-note delay at 120 BPM is 500 ms, and the same delay at 140 BPM is 428.57 ms. Producers often start from a hertz value instead: a 2 Hz tremolo at 120 BPM matches quarter notes, and 4 Hz matches eighth notes.

Metronome calibration is another. Count 30 beats against a stopwatch. If they take 15 seconds, the tempo is 30 / 15 x 60 = 120 BPM. If they take 20 seconds, the tempo is 90 BPM. The same check works for a tapping test or a metronome that feels off.

In video and animation, a cut on every beat at 100 BPM repeats at 1.6667 Hz, which is 40 frames at 24 fps (1.6667 x 24 = 40). A flicker effect set to 1 Hz reads as 60 BPM, and a 2 Hz pulse reads as 120 BPM.

Physics and engineering use the same arithmetic for any periodic event. A shaft turning 1800 times per minute runs at 30 Hz. A heart beating 75 times per minute is 1.25 Hz. The conversion does not care what the cycle is, only that it repeats at a steady rate.

Sample libraries add one more case. A one-shot with a 0.5 second tail fits inside a beat at 120 BPM and spills over at 140 BPM, where the beat is 428.57 ms. Checking the tail against the beat length prevents a cut that clips the decay.

Note Values at Three Common Tempos

Note values are fractions of a beat, so their length in milliseconds depends on both the note and the tempo. The table lists the values a delay or arpeggiator usually offers at 90, 120, and 140 BPM. Read across a row to see how much the same note value changes when the tempo moves.

The dotted eighth at 120 BPM is 375 ms, a staple setting for rhythmic delay. The same note at 140 BPM is 321.43 ms, about 54 ms shorter. That gap is audible on a repeat pattern, which is why synced delays recalculate when the project tempo changes.

Triplets do not land on the same grid as straight notes. An eighth-note triplet at 120 BPM is 166.67 ms, while a sixteenth note is 125 ms. The triplet fits three notes in the space of two eighths, so its hertz value is 1.5 times the eighth-note rate.

Rounding Mistakes and Unit Traps

The first mistake is dividing by 100 instead of 60. A tempo of 120 BPM is 2 Hz, not 1.2 Hz. The second is using 1000 / BPM for milliseconds when the correct expression is 60000 / BPM. At 120 BPM the wrong form gives 8.33 ms instead of 500 ms, a factor of 60.

Rounding early is the third. 140 BPM is 2.3333 Hz, and 2.3 Hz is close enough for a label but not for a long session. The difference is 0.0333 Hz, which is one extra cycle every 30 seconds. On a four minute track that is eight cycles of drift.

Mixing hertz and kilohertz is the fourth. A 2 Hz tempo is 0.002 kHz, not 2 kHz. Audio plugins sometimes label LFO rates in Hz and audio frequency in kHz, and the two scales sit far apart.

Last, do not treat tempo hertz as pitch. Tuning a kick drum to 2 Hz is not the same as matching a 120 BPM track. Pitch comes from the fundamental frequency of the sound, usually 40 Hz to 100 Hz for a kick, while tempo comes from the spacing of events. Both can be measured in hertz, and they answer different questions.

A final check costs nothing: multiply the hertz answer by 60 and confirm it returns the tempo you started with. If it does not, the divisor or the unit conversion went wrong.