Tap Tempo BPM Counter

Beats per minute is the first thing a DJ, a drummer or an editor needs to know about a piece of music. If you do not have the number, you can find it with your finger: tap along with the music and the page works out the speed from the gaps between taps. The result also gives the length of every common note value in milliseconds, which is what a delay pedal, a plug-in or a click track asks for.

How the number is calculated

The page records the time of each tap and takes the intervals between them. A beat that lasts 500 ms is 120 beats in a minute, because 60,000 ms divided by 500 is 120. With the mean setting, the BPM is 60,000 divided by the average interval. The median setting uses the middle interval instead, so that one tap that came a little early or late does not change the answer. The tempo appears after two taps and gets steadier as you go; only the most recent 12 taps are used, and if you stop for more than 2.5 seconds the next tap starts a new count.

A worked example

Tap at an even rate of half a second and the display settles at 120 BPM. The tempo word is Moderato / Allegro, because the boundary of 120 BPM belongs to both ranges in the table. A beat is 500.0 ms and a bar of 4/4 is 2.00 s. The note-value list shows the eighth note at 250.0 ms, the dotted quarter at 750.0 ms and the quarter-note triplet at 333.3 ms. Those are the delay times to set on an echo that should lock to the music.

Choosing the beat to tap

Tapping the wrong level of the rhythm is the common error. Most pop songs have a steady kick or snare pattern, and the quarter note is the pulse you feel. Some music, such as slow ballads, may feel like eighth notes at twice the speed; either number is right as long as you know which you mean. A song in 6/8 usually has two big beats per bar, each of three eighth notes.

Tempo words

The table of Italian tempo marks gives ranges such as Andante 76 to 108 BPM, Moderato 108 to 120, Allegro 120 to 156 and Presto 168 to 200. These ranges are conventions and overlap, since composers, metronome makers and publishers draw them differently. Use them for orientation, not for precision.

Edge cases

On a phone, tap with a fingertip on the large button rather than the keyboard, as the touch is detected on contact. A typing delay of a few milliseconds is the same for every tap, so it does not change the intervals. Very slow tempos under 40 BPM and very fast ones above 200 are possible but hard to tap evenly; type the value if you know it. A song with a tempo that drifts, such as a live recording, has no single answer.

Limits

It does not listen to audio. The accuracy depends on your tapping, typically within a BPM or two for a steady piece after a dozen taps. Nothing is stored except the settings in your browser.

Related tools

• Delay Time Calculator gives delay and reverb times for any tempo.
• Polyrhythm Metronome plays two pulses against each other.
• Chord Transposer shifts a chord chart by semitones or capo once you know the tempo.
• Setlist Maker adds up song lengths for a gig.