Audio Latency Test
Start the metronome, then tap the pad in time with what you hear.
Negative offset = anticipating the beat. This measures your whole chain (output latency plus your own timing bias), so compare readings (Bluetooth vs wired) rather than trusting the absolute number; output latency may read n/a where the browser doesn't expose it.
How it works
仕組みMeasure how much delay sits between your browser and your ears. The tool reads the audio stack’s own numbers first (AudioContext baseLatency and outputLatency), then runs a hands-on check: a metronome ticks at 90 BPM and you tap along, and after eight taps it reports your mean offset from the beat in milliseconds. Latency depends entirely on your device, driver, and output. Wired headphones commonly sit under 30 ms while Bluetooth can add 100-300 ms, so no spec sheet can tell you what your setup actually does. Rhythm-game players and musicians, this one’s for you.
baseLatency is the delay the browser’s own audio pipeline adds (typically 3-12 ms), while outputLatency estimates the rest of the trip through the OS mixer, driver, and hardware to actual sound. Not every browser reports outputLatency (it may read n/a or 0), and it often only settles once audio is playing. Their sum approximates the true click-to-sound delay, but the tap test captures things the numbers miss.
A negative offset means your taps land before the scheduled tick: you’re anticipating the beat, which is completely normal for a steady rhythm since the brain predicts rather than reacts. Trained musicians often sit slightly ahead or dead-on, while high output latency pushes the number positive because you hear each tick late. That’s why the relative change matters more than the raw value.
Run the tap test once on each output, keeping everything else identical, and compare the two offsets; the difference between them is a decent estimate of the extra delay your Bluetooth link adds. Expect roughly 100-300 ms more depending on codec (AAC and SBC are slower; aptX Low Latency and LE Audio are much better). For rhythm games and recording, wired remains the safe choice.