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Online Tone Generator

Screenshot of the Online Tone Generator

I made an online tone generator based on the Firefox Audio API HTML5 Web Audio API. It’s basically a large logarithmic slider that allows real-time, smooth frequency changes.


  • Fine-tune the frequency in 1 Hz, 0.01 Hz and 0.001 Hz increments
  • Pick a music note from a list (added Sep 2014, revamped May 2016)
  • Increase/decrease the frequency by one octave (added Aug 2015)
  • Can change the frequency smoothly as you move the slider
  • Keyboard shortcuts (added Aug 2015)
  • Generate a link to a specific tone, so you can share it (added May 2016)
  • Choose sine/square/sawtooth/triangle wave (added Aug 2017)
  • Input frequency as a number (added Aug 2017)
  • Works well on Chrome, Firefox & Safari – including mobile devices (iOS, Android) – requires a browser with support for the Web Audio API.

There are other tone generators on the Web, but they are not as cool (if I do say so myself) and/or they require Java or Flash.

What can you use a tone generator for? You can do a science experiment with resonance, tune a musical instrument, test your new audio system (how low does it go?), test the limits of your hearing (I can hear virtually nothing above 18,000 Hz, even at maximum volume), or figure out your tinnitus frequency to better target therapy.

780 Comments so far

  • Justen

    I love this site! Thanks so much.
    Just one suggestion: would be cool to be able to divide it between left and right speakers so we can test two speakers against each other.

  • V.D.

    Hi! I have a pair of Audioengine A5+ speackers connected to my PC through a Ifi Zen DAC V2. Is it possible that I damaged my left tweeter with this test (high frequsncy + high volume)? Apparently the left tweeter doesn’t work. Could the other’s speakers quality be affected by the test even if apparently they produce a pretty normal sound?

  • revenger

    I use this tool to take revenge on my annoying upstairs neighbor who make loud drop noises all night and morning

  • Xilef

    I would love to see a feature, where you could set phase difference between the left and right speakers, for some more fun experiments about interference

  • Ken

    Really useful tone generator. I am using it to check the notches in my hearing frequency spread. It would be useful to be able to save the level/frequency pair in a file or clipboard on (say) doing a shift click after adjusting the frequency and level. It would be easy then to use a spreadsheet on the collected data to plot the result. But I am doing it by hand which is fine.

    I sent you a small donation.

  • Roy

    have any of you guys in here tried the test that this guy is doing??

  • Lukas Sitkomirski

    Dzięki za twoja prace! Mam jednak prośbę. Proszę daj możliwość zmiany frekwencji dźwięku poprzez przesuniecie suwaka i w tym samym momencie odczyt danej frekwencji na liczniku. Teraz przesuwam suwak w lewo albo prawo, ale frekwencja pozostaje przy 440Hz. Trochę to irytuje.

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