Online tone generator
One steady sine wave at whatever frequency you set. Useful for testing speakers, checking the top of your hearing, tuning by ear, or sitting with a drone.
A tone generator plays a single sine wave at one frequency. Set the carrier slider to the frequency you want and press play — the sound is synthesised in your browser, so there is nothing to download and no compression between you and the waveform.
What people use a tone generator for
| Task | Frequency | How |
|---|---|---|
| Check a speaker or headphone | 50–120 Hz, then higher | Sweep the slider by hand and listen for rattles or silence |
| Tune an instrument | 440 Hz or 432 Hz | Play the reference and match by ear |
| Compare two pitches | Any | Use the preset buttons to switch instantly |
| Test a stereo image | Any | Use the headphone test instead |
| Sit with a drone | 100–300 Hz | Add a noise bed on the mixer if it feels bare |
Two boring, real safety notes. Start every test at a low volume — a high tone at full output is genuinely painful. And do not use this page to diagnose a hearing problem: a browser tone through unknown headphones measures your equipment as much as your ears.
Sine only — and why that is the right default
Every tone here is a pure sine wave: one frequency, no harmonics. Square and sawtooth waves are richer and considerably louder at the same nominal level, and they are also much harsher and much easier to hurt yourself with. For testing gear and for listening at length, sine is the honest waveform.
Two tones instead of one
If you want a small difference between the ears rather than a single pitch, that is a binaural beat — the main generator does it. Set the beat to 0.5 Hz for a slow wobble or 40 Hz for a rough flutter. The tone generator is the same engine with both oscillators matched.
Questions
What frequency range does this cover?
The slider runs from 40 Hz to 1000 Hz, which covers tuning, speaker checks and every frequency this site has a page for.
Is a browser tone generator accurate?
The frequency is as accurate as your device clock, which is very. The level is not guaranteed — volume depends on your headphones, your operating system and your browser.
Can I leave a tone running?
Yes — set the timer to “No limit” and it runs until you stop it. There is no session cap.
Why does a high tone sound quieter than a low one at the same volume?
Because human hearing is not flat. Sensitivity peaks in the mid range and falls off at both ends, so equal signal levels do not sound equally loud.