To play a constant tone, click
or press Space.To change the frequency, drag the slider or press ← → (arrow keys). To adjust the frequency by 1 Hz, use the buttons or press Shift + ← and Shift + →. To adjust the frequency by 0.01 Hz, press Ctrl + ← and Ctrl + →; to adjust it by 0.001 Hz, press Ctrl + Shift + ← and Ctrl + Shift+ → To halve/double the frequency (go down/up one octave), click
and .To change the wave type from a sine wave (pure tone) to a square/triangle/sawtooth wave, click the
button.You can mix tones by opening the Online Tone Generator in several browser tabs.
Tuning instruments, science experiments (what’s the resonant frequency of this wineglass?), testing audio equipment (how low does my subwoofer go?), testing your hearing (what’s the highest frequency you can hear? are there frequencies you can hear in only one ear?).
Tinnitus frequency matching. If you have pure-tone tinnitus, this online frequency generator can help you determine its frequency. Knowing your tinnitus frequency can enable you to better target masking sounds and frequency discrimination training. When you find a frequency that seems to match your tinnitus, make sure you check frequencies one octave higher (frequency × 2) and one octave lower (frequency × ½), as it is easy to confuse tones that are one octave apart.
Alzheimer’s disease. Some scientists from MIT are seriously investigating the possibility that 40 Hz tones may reverse some of the molecular changes in the brains of Alzheimer’s patients. Initial studies on transgenic mice showed promising results, but (as is often the case) early-stage human trials paint a much murkier picture. Further studies are underway. Here’s a summary of the research so far and a report from a user who tried 40 Hz therapy on his wife. (Note that this tone generator is not a medical device – I don’t guarantee anything!)