Metronome

How it keeps time

The click is scheduled on your device's audio clock, not on a counting loop: every tick gets an exact moment, and the page simply works a few steps ahead. That is why a slow or busy browser cannot make the beat wobble — each click lands where it belongs. The trade-off, stated honestly: in a background tab the browser may pause the scheduler, so the tick can fall silent there; it resumes cleanly, in step, when you come back.

Tap tempo works like a bandmate counting you in: click it a few times at the speed of the music and the middle interval between your taps becomes the tempo. Pauses longer than two seconds start the count over. Subdivisions add quieter clicks between the beats (eighths, triplets or sixteenths), and the first beat of the bar can carry a higher accent so you always know where "one" is. A quiet practice-room setup uses the volume slider; at zero the beat still shows on the dots.

Sound needs one interaction with the page first (pressing start is enough) because browsers only let a page play audio after you have engaged with it. The page makes no network requests at all.