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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.

522 Comments so far

  • Golu

    Can you please tell me if it is possible to generate the same frequency, buy out of phase with the original. Say, a sliding adjustment that can produce the same frequence 45,90,180 out of phase. Theoretically , one could null out a frequency, like some high-end pro audio microphone filters. I wonder it this app could be updated to do that. The ability beat both frequencies (in phase , out of phase) together would be a wonderful capability. It may also help to provide research into other forms of sound masking.

  • Ric

    Thank you for creating this.
    I don’t have Control or Shift Keys on my phone. Is there a work-around to set the signal between the 1Hz increments?

  • Kion Larsen

    I have problems with some mice 🙂

    And I have bought a digital cat (ultrasonic mice repeller). This, according to the box, generates an ultrasonic sound in the area between 20 – 70 kHz.

    Am I able to generate this sound level using a computer, your website and some speakers?

  • Kion Larsen


    Can I use you website to generate ultrasonic sounds?

    Or can I “just” make sounds in the 30 to 65 kHz area?

  • Pedro

    Great program but missing the function to select half-wave.
    Example: I need positive square wave for therapy.

  • Ale

    Thanks for this site Tomasz! I was diagnosed with tinnitus (36-37hz) and this is the only thing that I found helpful to sleep at night!

  • alex

    it would be good to be able to trigger a sound at a given frequency by simply activating a link such as
    For instance: would select an A4 at 440Hz and play it. The user could then press the STOP button. Thanks

  • Fred Tatar

    I must compliment you. Of the many apps I have tried for various uses, yours is well designed and implemented. I have had hearing problems for sixty years, and have seen doctors, hearing aid specialists, etc. I have confidence in my ability to conduct experiments to aid in my understanding of why I can’t hear. Tonight I said it would help if there was something on my computer that would generate tones. So with a simple search, your app came up, and I am amazed how well done and useful this is. So I thought I had to tell you.

  • Partha Sarathi

    Can playing this sounds damage my earphone?

  • Bill Gambrell

    Thank you for putting this on the web. It is most interesting and helpful. I was a musician in my teens and 20’s and always had good hearing. I am now almost 70. I used your tone generator to check my hearing. I “rated” 9955 Hz in my left ear and 11,119 Hz in my right ear. However, when I used both ears equally I heard up to 11,200 Hz. Is this result typical, i. e. that one might hear slightly better using both ears or to you think I’ve fallen prey to some type of placebo effect? Thanks again for taking the time to do this. I found it most interesting! Bill Gambrell

  • Renso van Veen

    hi! i like this app/website a lot, my subwoofers/woofers react to it like it’s part of them, BUT a sweep option on the website and in the app would be really cool to see, since some people would like to know if their subwoofers/woofers can handle the travel from for example: 5Hz to 60Hz with out moving it themself

  • Michael

    I used this website to clean water out of my earbuds! thanks!

  • Gabriel Mervin

    Hey Tomasz, I love your tone generator, and I just have one suggestion. I don’t know of you’ve considered it, but if it’s not too much, you should develop a mobile app. It doesn’t even have to be very different, just something that you can run online or off. I love your work and this is great either way, but I frequently camp or go off the grid, but I don’t have a data plan. If i did get one, many of these places don’t get support on any modern bands anyway. You could also make it ad supported, though you wouldn’t get ads miles from civilisation. Or not. I support you either way. You could also have merchandise such as hats or shirts. not only could you get a cut of it, but it’s also free advertising. I suggest something simple like the waveform pattern and the url on a solid background. That was actually 3 suggestions, but I think they are all great ideas and you would get a lot of support with each. I look forward to the future of your sites,


  • Stephen Davison

    Hi! I like this tone generator. Just would love to have A 0.1Hz adjustment capability


  • Vuuvi

    I love this, I used it to mess with my vocal range (about D2-D6) and tuned my guitar. Simple and Perfect.

  • Gregory Whitchurch

    This just in:

    I’ve been running this generator for my late-90s parents w/ (admittedly anecdotal) success for almost 2 yrs. now. Thanks so much for your support, Tomasz.

  • Peter B

    Thank you! I had a LF Tinnitus and you website helped to understand whrere the problem is and showed me how i cured. =)

  • Jay Maupin

    Mr. Szynalski:

    This is perfect for my particular needs:

    I am a long time harmonica hobbyist, who is now studying to be professional level.

    Many notes on a harmonica can be “bent”; that is, a hole can be played by modifying the air hole such that the pitch can be lowered or changed. To be a professional one must, of course, be able to “bend” a note accurately to the desired pitch. And like most harmonica players, I have harmonicas in many keys. Your tone generator, especially with your chart of all the pitches, gives me a tool that lets me easily check my pitch on any “bend” on any one of my harmonicas.

    A very useful tool for a harmonica student. I’m taking an online course, and I will send them a link to your site.


    Jay Maupin aka”Crazy Uncle Jay”.

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