Station Audio

Online metronome

Set a tempo and a time signature and press start. The space bar starts and stops it. Tempo and metre changes take effect on the next click.

Tempo

120 BPM

One beat every 500 ms; one bar of 4/4 every 2.00 s, or 30.0 bars a minute. Traditionally Moderato or Allegro.

Tempo markings

The ranges traditionally printed on mechanical metronomes. They overlap, and composers, editions and eras disagree about them, so read them as rough guides rather than definitions.

MarkingMeaningApprox. BPMms per beat
Largo broad, very slow 40–60 1500–1000
Larghetto rather broad 60–66 1000–909
Adagio slow, at ease 66–76 909–789
Andante at a walking pace 76–108 789–556
Moderato moderate 108–120 556–500
Allegro fast, bright 120–168 500–357
Presto very fast 168–200 357–300
Prestissimo as fast as possible 200–240 300–250

How to use it

Type a tempo, use the − and + buttons, or drag the slider, then press Start or the space bar. BPM here means clicks per minute on the beat: in 4/4 that is the quarter note, and in 6/8, 7/8, 9/8 and 12/8 it is the eighth note. The subdivision setting adds quieter clicks between beats: two per beat for eighths, three for triplets, four for sixteenths.

The first beat of the bar is the loudest and highest click. In signatures that split into groups the first beat of each group gets a lighter accent: 4/4 as 2+2, 5/4 as 3+2, 6/8 as 3+3, 7/8 as 2+2+3, 9/8 as 3+3+3 and 12/8 as four groups of three. Untick the accent box if you want every beat the same.

How the timing works

The metronome uses the lookahead scheduling technique for the Web Audio API. Every 25 ms a short timer asks: which clicks fall within the next 100 ms? Each one is booked on the AudioContext clock at its exact time, and the audio hardware plays it there, however busy the page is. The interval between clicks is simply:

Worked example. At 96 BPM in 7/8, each eighth-note click is 60 / 96 = 0.625 s apart, so a bar of seven lasts 4.375 s, and the accents land on clicks 1, 3 and 5 (the 2+2+3 grouping). Adding triplet subdivision gives 60 / (96 × 3) ≈ 0.208 s between clicks.

Where it stops being reliable

The spacing between clicks is as steady as your device's audio clock, which is far steadier than any player needs. What can go wrong is everything around it. Browsers slow timers in background tabs; the metronome books clicks further ahead when the tab is hidden to ride this out, but a tempo change made then can take a second to be heard. Bluetooth audio delays every click by the same amount, so the clicks stay even but arrive later than the lights. A phone that goes to sleep will stop the audio.

To find the tempo of a recording rather than set one, use the tap tempo counter. To turn a tempo into delay times for effects, use the delay time calculator.

Common questions

5 answers
Why does this metronome not drift like some browser metronomes?

Because the clicks are not timed with JavaScript timers. A timer only wakes up every 25 milliseconds to look ahead; each click is then booked on the audio hardware’s own clock, which runs independently of whatever the page is doing. A metronome that plays each click the moment a timer fires inherits the timer’s jitter, which can be several milliseconds and occasionally far more.

In 6/8, should the BPM be the eighth note or the dotted quarter?

On this metronome the BPM is always the clicked beat, which in 6/8, 9/8 and 12/8 is the eighth note. Music in 6/8 is usually felt in two, with the tempo given for the dotted quarter. To get a dotted-quarter tempo of 60, set 180 BPM here: three eighths per dotted quarter. The accents on beats 1 and 4 mark the two big pulses.

What is the difference between 6/8 and 3/4?

Both have six eighth notes in a bar. 3/4 groups them in pairs (three beats of two eighths), while 6/8 groups them in threes (two beats of three eighths). On this page, 3/4 accents only beat 1; 6/8 accents beat 1 strongly and beat 4 more lightly so you can hear the 3+3 grouping.

How should I practise with a metronome?

A common method is to find the fastest tempo at which you can play a passage cleanly, drop 10 to 20 percent below it, and work back up a few BPM at a time. Another is to set the click to beats 2 and 4 only, by halving the tempo and treating each click as a backbeat, which forces you to keep the time yourself. Neither is the one right way; teachers disagree about how much to rely on a click.

Can I use it with headphones or Bluetooth speakers?

Yes, but Bluetooth adds latency, often 100 to 300 milliseconds, so the clicks reach you later than the screen flashes. The clicks remain evenly spaced, which is what matters when you play along by ear. If you also watch the flashing beat indicator, use wired headphones or the device speaker.

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