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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.


384 Comments so far

  • Mark

    Wow. I test square waves for my piezoelectric buzzer and so far it works great. Awesome site.

  • Jack

    Hmmm. It might just be my computer, but this sounds a little sharp. 440Hz to my ears sounds like 435 on this device. It might just be me, but maybe someone can look into this?

  • Stepan

    This is brilliant. I wanted to match a gamma frequency tinitus and this worked! Gamma should be nested in theta or alpha, whereas tonic gamma indicates pathology and there are many other than just Alzheimer’s. Jay Gunkelman talks about this on YouTube.

  • Jeff Keen

    This is a fun website. Is there a reason the default frequency is set at 440 Hz?

  • Antonio Pina

    I start to play with frequencies to my dynaudio bm15a monitors, and after a while I breakdown my monitors!!!!
    Both stoped, it blow some fuses and more…!!!

  • Arnaud-Alexandre Kozic

    I use your tone generator with my pupils in physic’s lesson in middle school in France (age 10 to 15 y old)
    Thank you for this useful tool.

  • Metten

    Hi there,
    I use the online tone generator with a Rubens tube. One thing I could not find is an option to produce multiple frequencies. I have to use a frequency generator app on my cellphone to do this. It is for showing the effect of beats. Is it possible for you to upgrade the tone generator to a multiple tone generator?

  • Érik

    I leave in Brazil
    And i try write my opinion
    Good, must functional, easy and clean interface

  • Dawid

    Dziękuję za darmowe i bardzo przydatne narzędzie jakim jest generator tonów online.

  • John Cadd

    I am delighted with this wonderful tone generator but it only worked for ten minutes and then the sound stopped. I have an old Acer Aspire on Linux and Chrome. Hope it will crank up again soon . I`m missing it already . I sent $5. within minutes of finding the generator . It`s not much but it`s early days yet .

  • John Cadd

    I could not get it to worl properlt on my pc but then tried headphones and it`s perfect.
    There must be some circuit that interferes . Great site . Thanks .

  • John Hardegree

    This is a fantastic resource! I have two distinct forms of tinnitus, and I also I’m a writer on Just a few minutes ago, I wrote an answer to someone who is asking how they can explain to someone what their tinnitus sounds like.

    I did a search and found this site and was able to generate two web links that when played together, do a very good job of approximating what I actually hear most of the time.

    Two suggestions I would have, would be that you move the arrow buttons that raise or lower the frequency. The way they are now, when trying to fine-tune the frequency using those arrow buttons, it’s very difficult to avoid hitting the text field that contains the actual frequency.

    (Using chrome on my cell phone)

    Also, the slider that allows you to control frequency by siding left to right and also the volume slider, are extremely sensitive, and very difficult to use accurately.

    That’s just constructive criticism, but please don’t let it detract from the fact that I really seriously appreciate you making this available. I sent a little something to you with PayPal, to help out a little.

    Also, I put links to the two tones that I hear, in my answer on Quora. I also at the bottom said that I would appreciate it if people would donate to your site, and I put a link for that as well. I assume that’s okay with you, but if not let me know and I’ll change it in any way that you want me to.

    My tinnitus answers don’t usually get a whole lot of views, so don’t expect to get rich or anyting but maybe a couple people will donate based on that.

    I put the link to my quora answer in the website field above.

    Thanks again!

    • Tomasz P. Szynalski

      Thanks for the donation, John, I appreciate it. I agree that the up/down buttons are too close to the frequency readout. I’ll probably add more space to prevent accidental clicks. The sliders on mobile will always be harder to use than on your computer due to the small screen size. On my phone, they work well enough, especially given that you can fine-tune the frequency using buttons. The sliders are third-party components. It’s possible that they could be improved if I made my own sliders from scratch, but that would take a fair bit of time, so it’s probably not going to happen soon. Also, there’s no guarantee that the granularity would be any better because it could be an issue with how touch is implemented on mobile devices. It’s quite likely, in fact.

  • Chris K

    dear tomasz,
    very nice feature to choose the music notes.
    it would be perfect if it could be combined with an option to choose A4=440Hz, 441Hz, 442Hz 443Hz or 444Hz.
    I use this to practice intonation on my saxophone, but often i need to play in tune with A4=442Hz or 443Hz – would be amazing to be able to set it to other values and then choose any note from there..
    is it clear what i’m saying? 😉
    thanks anyway for this great site!!

  • tom hennessy

    I’m presently using a light and sound brand wave entrainment machine to help my wife with her Alzheimer’s. The 40 htz frequency has been reported to be beneficial so I tune the device to 40 htz and run it for 30-45 min. I’d like to over lay this with your tones. I can input to the device from a cd or a cassette. Is there a way I can down load one or more of your frequencies and try this out?
    Thank you
    tom hennessy

  • Graham Dudfield

    Excellent . Just what I have been looking for.

    I have just had (very expensive ) hearing aids fitted and I have been testing with the different frequencies with and without the aids.
    When I had my hearing tests, the Audiologist randomly pick frequencies, volumes and L or R ears, sort of a blind testing.
    the standard test frequencies are
    500,1000,1500,2000,3000,4000,6000,and 8000hz
    Not sure why they dont test a lower frequency say 200Hz.

    I think that with this website I can test my own hearing more accurately by setting the frequency and turning the volume up and down (on the computer) and recording the lowest volume which I can just hear for each frequency for each ear. (I needed to have the volume on the generator set to 25%)

    I have also found my Tinnitus frequency by sliding the Hz up and down , finding the point where the tinnitus sound disappeared . 2349Hz in my case.

    Not sure why the Audiologist didn’t do this.

    So I’m going to take the results to my Audiologist and have my aids fine tuned
    on the basis of my tests, and also recommend that they look at the website.
    Donation coming thank you

    Cheers Graham

    • Tomasz P. Szynalski

      Hi Graham,
      Thanks for the donation.
      Actually, I don’t think the results will be more accurate, because the speakers on which you’re listening have a non-flat frequency response, which will skew the results. Also, you don’t have an absolute reference — there’s no way to tell how loud (in dB SPL) the sound that reaches your ear is. All you can do is compare your hearing at e.g. 8 kHz with your hearing at 1 kHz. But if your hearing is impaired at both 8 kHz and 1 KHz, you won’t be able to detect it.

  • Jodro

    Nice and simple layout. Been using this squarewave to drive my solid state tesla coil. At high frequencies my touch screen stops working so i’ll be using hardware soon. Until then, Szynalski it is!


  • Diaa

    I have loved using this, as all the apps kinda suck for one reason or another… BUT… I don’t know why, but lately, it seems like there is a problem that is getting worse each time I use it – the longer I leave it playing (I use it to help me sleep), the more the sound “POPS”… And it’s turning out to be more of a detriment to my sleep because of that, than a help… PLEASE fix this! :'(

    • Tomasz P. Szynalski

      Sorry to hear that. It’s probably due to some kind of power-saving measure in whatever device/browser combination you’re using. The popping happens when the program cannot deliver new pieces of the tone fast enough (probably because the device has slowed down the CPU), so eventually there is a break. Using a different browser (if that’s an option) could help. There’s nothing I can do about it on my level.

      • Diaa

        I understand, and thank you for your time replying. Unfortunately, I’ve experienced it not only on my Android Chrome browser (which is what I normally use, for convenience’s sake), but also my Dell laptop’s Chrome browser (Chrome is all I use anymore, now that Firefox seems to want to be slower than it used to)… and it’s pretty hefty to be a laptop. $800 worth of heft, lol. And just barely over a year old, and I do weekly maintenance and am completely OCD about keeping it “clean”. Though, I will admit, the popping happens FAR LESS on the laptop, than on the phone… so maybe I’ll just start lugging it into the bedroom at night, anyways. Haha. Thanks again for your time and reply. 🙂

        • Tomasz P. Szynalski

          Gotcha, so it appears to be an imperfection in the audio code in Chrome. I’m not surprised – Chrome is not primarily designed as a background music player. If you’re so inclined, you can try and file a bug report here:

          Would it solve your problem if you could download about an hour-long WAV audio file with your desired tone? You could then play it on repeat in your audio player of choice (it might even work on some portable players). However, every hour or so there would be a slight gap (not an abrupt one, but a quick fade-out followed by a fade-in) because of the track ending.

      • Diaa

        Oh, and I may also try a different browser as well… If it’s just for this alone, I can do that much at least.

  • Merlin Marquardt

    Very nice tone generator. Very cool idea. Have you considered making a visual frequency (color) generator?

  • Johan Halmén

    Please, add a button, which adds the fundamental frequency. Starting with say 120 Hz, you’d get 240, 360, 480, 600, 720 etc. This would make audible the partial tone series, one of the most fundamental thing in western music.

  • Adam

    Hi Tomasz,

    I love your site – but I even more I would love to have it as a plugin – for Logic. To combine it – and also tune and control the internal tune of logic – while ajusting it to different tunes. You do not plan to do something like that? Thank you for your cool site.

  • Suzanne

    I wish this would not be louder when playing a higher pitch. I’m a teacher and am looking for an interactive like this that allows students to investigate how changing the pitch and volume of a sound (independently) change the shape of the waves themselves. Whenever I double the pitch (440 to 880, say) the volume also increases, which means both the wavelength and amplitude of the resulting waves change (I’m using this in coordination with an online oscilloscope). I do appreciate the tool though (it’s better than having students try to change their pitch themselves).

  • Chewba

    have this tinitus conditions for almost two years, and your tool it helps me to have control on it, its soften my nights, same my sister’s.

    Thank you so much for this very healthy tool

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