BPM Calculator: Beat Duration and Note Delay Times
Enter a BPM and time signature to instantly get the beat duration in milliseconds and seconds, bar length, and the exact delay times for whole, half, quarter, eighth, sixteenth, and 32nd notes, including their dotted and triplet variants. Use it when programming synthesizer delays, setting reverb pre-delay, or matching a metronome to a song tempo.
Formula
Worked example
120 BPM: beat duration = 60 000 / 120 = 500 ms. In 4/4 time, one bar = 500 x 4 = 2 000 ms. An eighth note = 250 ms, a dotted-eighth = 375 ms (the classic echo pedal setting), a 32nd note = 62.5 ms.
What is BPM and why does it matter?
BPM stands for beats per minute, the universal measure of musical tempo. One beat is the basic rhythmic pulse of a piece: in most pop and dance music it is the quarter note, the note that falls on each click of a metronome. A BPM of 120 means the metronome clicks 120 times per minute, or twice per second. Knowing exact BPM lets musicians tune delay and reverb effects to subdivisions of the beat, match the tempo of two tracks for DJ mixing, set a metronome for practice, and understand where a song sits among genre conventions.
How to use the BPM calculator
Type your BPM into the field above and choose a time signature. The calculator instantly shows the beat duration in milliseconds, the full bar length, and the delay times for every note value from whole notes down to 32nd notes, each in its normal, dotted, and triplet form. The delay table below the inputs lists all twelve values in one place for quick reference when programming effects. To find the BPM of a song you do not know, use a tap-tempo tool: tap a key in time with the beat for 8-12 taps, copy the resulting BPM into the field, and all delay times update automatically.
Syncing delay and reverb to the beat
Tempo-synced delay is one of the most practical uses of BPM math. Set the delay time to the quarter note value for a clean "doubling" echo, or use the dotted-eighth note time for the shimmering slapback heard on countless pop and country guitar parts. Reverb pre-delay is typically set to a small fraction of the beat, often a 32nd or 64th note value, so the initial transient punches through before the reverb tail begins. All of these times are listed in the delay table generated by this calculator for your exact BPM.
Time signatures and bar duration
The time signature tells you how many beats are in each bar and which note type counts as one beat. In 4/4 (the most common time), there are four quarter-note beats per bar. In 3/4 (waltz time) there are three. In 6/8 the eighth note gets the beat and there are six per bar, which gives the music a compound, rolling feel. The bar duration above updates when you change the time signature, so you can set long reverb tails to expire just before the next bar starts.
Dotted notes and triplets
A dotted note lasts 1.5 times as long as the plain note. A dotted quarter note therefore lasts 1.5 quarter notes, and a dotted eighth lasts three sixteenth notes. Triplets divide a note into three equal parts where two would normally fit, so each triplet note is 2/3 of the plain value. A quarter-note triplet at 120 BPM lasts 333 ms instead of the usual 500 ms. Both values appear in the delay table and are particularly useful when programming polyrhythmic drum patterns or syncing arpeggiators.
Genre BPM ranges and classical tempo markings
| Tempo marking / Genre | BPM range | Feel |
|---|---|---|
| Grave | 20-40 | Very slow, solemn |
| Largo | 40-60 | Broad, slow |
| Adagio | 66-76 | Slow and stately |
| Andante | 76-108 | Walking pace |
| Moderato | 108-120 | Moderate |
| Allegro | 120-156 | Fast, lively |
| Vivace | 156-168 | Very lively |
| Presto | 168-200 | Very fast |
| Prestissimo | 200+ | As fast as possible |
| Hip-hop / R&B | 60-100 | Laid-back groove |
| Lo-fi hip-hop | 70-90 | Chill, relaxed |
| Pop (mainstream) | 100-130 | Energetic, radio-friendly |
| House | 118-130 | Dance floor, four-on-the-floor |
| Techno | 125-150 | Driving, industrial |
| Drum and bass | 160-180 | Breakbeat, fast |
| Reggae | 60-90 | Relaxed, offbeat |
| Punk rock | 150-180 | Aggressive, fast |
| Waltz (3/4) | 84-108 | Triple-meter dance |
Typical BPM windows used in common genres and classical Italian tempo terms. Ranges are conventions, not strict rules.
Frequently asked questions
What is a BPM calculator used for?
A BPM calculator converts a beats-per-minute value into time-based delay values for every note subdivision. Musicians and producers use it when setting delay pedal times, reverb pre-delay, DAW-synced LFO rates, and metronome tempos. DJs use it to check whether two tracks are close enough to blend without pitch shift. Fitness instructors use BPM to match music energy to exercise intensity.
How do I find the BPM of a song?
The fastest method is tap tempo: tap a button or key in time with the beat for at least 8-12 taps, and the average tap interval gives the BPM. After 4 taps accuracy is within about 5 BPM; after 12 taps it narrows to around 1-2 BPM. Many DAWs and audio analysis apps can detect BPM from an audio file automatically with 95 percent or better accuracy.
What delay time should I set for a dotted-eighth echo?
Multiply the quarter-note delay time by 0.75 (equivalently, take the eighth-note time and multiply by 1.5). At 120 BPM that is 375 ms. This value is shown in the delay table generated by this calculator. The dotted-eighth delay produces the characteristic "slapback" echo heard on many clean electric guitar parts because the echo lands on the "and" of each beat, reinforcing the groove rather than clashing with it.
What is the difference between BPM and tempo?
Tempo is the general concept of musical speed, while BPM is the numeric measure of tempo. A tempo of Allegro tells a performer to play "fast and lively"; the BPM equivalent (roughly 120-156) tells a metronome exactly how fast that is. Classical scores use Italian tempo words, modern and popular music usually specifies BPM directly, and a BPM calculator converts between the two.
What BPM is used in common music genres?
Hip-hop and R&B typically sit between 60-100 BPM. Pop ranges from 100-130 BPM. House and techno live between 118-150 BPM. Drum and bass runs from 160-180 BPM. Reggae is around 60-90 BPM. Waltzes in 3/4 time fall in the 84-108 BPM range. The reference table in this calculator lists the BPM windows for over a dozen genres and all major classical tempo markings.
How many beats per minute is a walking pace?
A comfortable walking pace is around 100-120 steps per minute, which corresponds to the Andante-to-Allegro range in musical terms. Fitness walkers aiming for a brisk pace often target music between 115-130 BPM. Runners at an easy jog typically match music around 140-160 BPM.