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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.

887 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.

    • Norman Rasmussen

      You could probably open the generator in two different windows to generate two different frequencies.

      Two identical frequencies will just attenuate each other depending on the phase. So you could just reduce the volume instead of requiring precise phase control.

  • 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?

    • Purleon

      Even if you could, how would you play it?
      Speakers are designed to play up to 24Khz at most (except for some exceptionally expensive electrostats and maybe some pro audio studio monitors with super tweeters; both of which I doubt you would have).
      There are devices that are made to make these sounds, but they’re not in the form of digital audio as the creator has pointed out.

  • 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.

    • Tomasz P. Szynalski

      Hi Greg,
      I’m sure people who visit this blog would love to hear about your anecdotal success. I know I would. Thanks for the link — that’s a well-written article that summarizes the research so far. Some new (for me) information about how microglia “listen in” on signals in the brain.

  • 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”.

  • Moi

    Thank you …

    Found your website whilst looking for ways to deter rats with high-frequency tones…

    I ended up finding a way to help manage my tinnitus.

    Thank you!


  • Alex

    FYI, the 40hz signal cats DO NOT LIKE at all. Mine began yowling as if in utter pain when I played it after reading the Alzheimers note on the bottom of the page. Please be aware if you have a cat, play it in headphones!

  • Etienne

    Thanks for that website I just discovered and that helps me with my tinnitus treatment !

  • Alfonso


    Have you considered being able to make it possible to hear a different frequency for each ear at the same time? I have a tinnitus in each ear, but they have different frequencies, and it would be very interesting to be able to cancel both tinnitus at the same time.

    Thank you

  • cleversausage

    Tried your tone generator for the first time, really like it! As had ideas. I listened to an audiobook/mp3 I had received as a free gift, that claimed you sleep/dream better using a 43hz frequency.
    I also read on some website offer about how 48hz can cause people who have insomnia, to fall asleep – they suggested add 3hz = 43 to 46hz – so I adjusted the tone generator to 48hz 🙂 To see if would make me doze off!
    So at the moment, am using your tone generator, trying many different tones from the real deep and bassy, to the semi high pitched to see what reaction bugs or insects,cats,and people, mainly women who are here frequently, to see how all react at certain frequencies.
    But might need help understanding what the different note selectors could do – effect something or someone else,or what sine,sawtooth,square or triangle will do…Can you give me some help hints,directions via link so I study more info on it/them? Thanks!

  • Valeriy Zilberberg

    It would be a good idea to ad a modulation option to the generator. The rest is just cool.

  • BigD

    Thanks! I’m using this for tinnitus, and it would be nice if the test tone could be played alternately (like half a second on, half a second off) so I could hear my tinnitus tone in the off parts which would make it easier to compare them. Alas, there is something very odd about tinnitus “tones” (at least for me) because a whole bunch of the test tones seem to match it! It’s kind of a ghost tone that is both a tone and not a tone. Your software really did help me chart my hearing loss much more precisely than a typical audiogram would. I tried building a notch therapy regimen on THAT (using a parametric Windows EQ program) since I couldn’t identify the tinnitus tone, but it didn’t seem to help. Still working on that. But thanks for so freely sharing this super useful functionality.

  • James David

    I have terrible neuropathy in my feet and legs and back from a combination Spondylolisthesis and diabetes type II. I was looking for a tone that could help with neural stimulation (a vagal neural stimulation) that could ameliorate my constant pain and ongoing neural damage. This site is very useful in conducting my ‘self-experiments’. Thank you.

  • John Noel

    Hi Tomasz, thanks for making this. It’s extremely useful for Physics demonstrations. I even use it to simulate speech with 3-d printed vocal tract models. However, there is frequent noise coming through even at low volume when I play it on my phone (but not on laptop). I’m guessing this is a symptom of it being a web-based because app-based tone generators don’t have this problem. I’d be curious to know what you think.

    John Noel
    Temple Physics

    • Tomasz P. Szynalski

      As a phonetics nerd, I would definitely watch a video of speech simulated with 3D-printed vocal tract models! There shouldn’t be any noise from your phone – my phone doesn’t do that. Have you tried another phone or another browser?

  • Ken Keicher

    Hi Tomasz,

    I noticed that when I put in a frequency, it shows that it is a specific note, but when I play that note on my electronic piano it is not in tune with that note; however, if I use your note chart and select a note from it and play along with it, it is perfectly in tune. Then when I switch back to the tone generator, it shows me the exact frequency that the note is.

    So I’m wondering why you put notes that supposedly represent a frequency on the main page, when they are not the exact note. An instrumentalist can’t tune with those slightly off frequencies, even though you have D4 or whatever in the box next to the frequency.

    For example, when I go to the note chart and click on D4, the frequency shown is actually 293.665 Hz and not 294 Hz which is shown on the main page, which will not produce that exact note. So why did you represent the note that way when it’s not the exact note?

  • Angela Del

    Hi, if I perform a frequency sweep and I leave the volume of the speakers constant. Should it result in the same sound pressure level (dB SPL measured at a given distance) for all the frequencies? Thank you.


    Well it’s not one of the best uses of this website but i’ve used to calibrate an trimming of
    Triaxial Accelerometers LSM6DS3 and ADXL345.

    I have written also a code to find the freqency with fourier transformation, and this help me to get the code running.

    Very thanks for the effor to make this app…

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