Tone Generator
A clean tone at any frequency from 20 Hz to 20 kHz — for testing speakers, ears and everything in between. Everything stays on your device. ← Workbench
Settings
Sweep
Glides from one frequency to another — handy for finding speaker rattles, cabinet resonance or the highest pitch you can still hear.
Notes on hearing and volume
The nominal range of human hearing is 20 Hz to 20 kHz, but the upper end declines steadily with age — many adults top out somewhere between 15 and 17 kHz, so if the highest part of a sweep is silent to you, that is normal and not a broken speaker. At the other end, frequencies below about 40 Hz are often felt more than heard unless you have a real subwoofer.
Start at a moderate volume and give your ears a break now and then. A sine wave is the purest sound — a single frequency and nothing else. The square, sawtooth and triangle shapes are built from that same fundamental plus a stack of overtones, which is why they sound louder and harsher at the same volume setting. Equal loudness also plays a part: the same level sounds quieter at the extremes of the range than in the middle, so a tone that seems faint at 40 Hz or 12 kHz is not necessarily weaker.
Sound needs one interaction with the page first (pressing play is enough) because browsers only let a page play audio after you have engaged with it. The page makes no network requests at all.