About TEMPOZOID

TEMPOZOID is a metronome you open in a tab. Set a tempo, press space, and it counts. Nothing to install and nothing to sign up for.

Why most browser metronomes drift

The obvious way to build one is a timer that fires every so many milliseconds and makes a click. It does not work. Browser timers are best effort: they are late when the page is busy, they are throttled in a background tab, and the small errors accumulate until the click is audibly wrong. A metronome that wanders is worse than useless, because you practise to it.

TEMPOZOID instead schedules its clicks on the audio clock, which runs in the sound hardware and does not care what the rest of the page is doing. A short timer wakes up now and then and books the next few beats in advance, at exact times. The result is that the beats land where they are supposed to whether or not the tab is in front.

The controls

• Tempo in beats per minute, adjustable with the arrow keys as well as by dragging.
• Tap tempo, for when you know the speed in your hands but not in numbers.
• Beats per bar, so the first of each group is accented and you can hear where the bar starts.
• Subdivision, to fill the beat with eighths, triplets or sixteenths.
• Volume, and the space bar to start and stop.

What Largo or Allegro means in beats per minute, and how many milliseconds a beat lasts, is on the tempo markings page.

It runs on your device

Everything happens in the page. The sound is generated in your browser rather than streamed, there is no server involved once the page has loaded, and your settings stay on your own machine.

Who makes it

TEMPOZOID is one of a small family of music tools built by an independent developer, alongside a guitar tuner, a guitar chord reference and a piano chord reference. There is also a joke version of this metronome that gradually loses its sense of time, which we do not recommend practising to.

Write to [email protected] with anything at all.