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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

  • Alice Franceschini


    I just found this website today. I bought some tuning forks and wanted to verify that the frequency the forks claim to be is a true claim. This works really well for that. Get your website tone going and make your tuning fork ring and listen to both. I have tested 2 forks so far and they are what they claim they are. Thank you so much for having this website.

  • Chris White

    On the Alzheimers thing – how about using binaural beats – open your TG in two browser tabs and set one for, say 460Hz in the left speaker/earphone, and 500Hz in the other, the brain hears the 40Hz beat. This certainly works for creating the beats (use frequencies closer together to really appreciate the beating) but what it would do for a sufferer, I don’t know.

  • mark

    i just have 1 question. for how much time can i leave my JBL speaker to play 50 HZ before destroying itself?

  • thomas

    Hi Tomasz,
    inspired by Dieter Broers I was looking for a tone generator and found yours.
    Maybe you could add the possibility to adjust the frequency of A4 to 432 Hz.
    This would be nice.
    Thanks a lot and kind regards

  • James David

    The sound stopped working. I’ve been paying a fee to support the site for a long time, but I can’t get any sound out of it anymore.

  • namewithheld

    Interesting self test for a suspected condition:

    Background Story:
    I had some repeated infections in my left ear over the years and there was a somewhat rapid (6mo) onset of partial hearing loss. (The loss made it difficult to hear voices in the presence of loud background noise such as at a restaurant.)
    For some time I have been asking doctors (primary care, audiologists, etc.) if the problem could be diagnosed as a “stiffening of the hearing drum” problem, they essentially said no but my opinion was they could “if they wanted to”, i.e., had the technology.
    There was something about the way things sounded that made me feel my ear drum had become more rigid or changed shape.

    So… now for the test:
    While wearing headphones that had cups which provided an airtight-ish seal I played a constant tone and then increased/decreased the air pressure. I did this by applying pushing/pulling forces to the headphone first against the left ear and then the right. (The right ear being my “standard”/reference ear.)

    What I noticed was there was a distinct increase in my ability to hear with my left when I decreased the air pressure but that was not the case for my right ear. An increasing the air pressure had a negative effect on both left and right. (i.e., My right ear was optimal at std. air pressure.)

    So, this has given me some evidence that left ear problem may indeed be due to the suspected (deformed drum) cause. How I will apply this information to my “tone deaf” 😉 doctors, I don’t know.
    _ _
    – –

    Thank you for web page. First time here.

  • Grateful

    Thank you for developing and maintaining this useful tool. It’s helpful as I work on broadening the range of my voice. I use this primarily on my phone.

  • Daniellus

    Good for tuning my sound system.
    Referring back to the tone generator, I can verify the amplification from my phone by using a spectrogram application. I do not know whether or not this is a good method, however as far as my ears go it sounds good. The best part of this tone generator when compared to other methods is the fact that it can hold a frequency as I’m tuning it and seeing the effect in the spectrogram app. Will use again.

  • Conor

    Can I use the tone generator for meditation?

  • Pekka

    Thank you for the good hearing test program. I would like the volume control to be logarithmic. It would make testing for hearing loss easier.
    At least in Finland, in medical studies, hearing is only tested up to the hearing limit of loudness, and this leads to incorrect hearing aid adjustments. The sense of hearing is not linearly proportional to the logarithm of sound intensity as expected. I have had my hearing tested for almost 10 years, I can only understand the speech of certain people without noise in conversations between two people.

  • Roland E Chemali

    I love this site and I have sent a small stipend for support. This morning it works well on my PC but it is totally silent on my iPhone. Please help.

  • Jae

    Is there a way to use the tool offline?

  • Mike Boddy

    This site is excellent, it has the tones I use and need to design steam engine whistles.

    I there a way you can save a tone and add a second or third tone to it. I’m trying to make a three tone engine whistle and would like to hear it generated before I make it.

  • Henry

    Could a feature be added to allow changing the phase of the tone?

    Having the same frequency running in two tabs and then adjusting the phase of one back and forth would be useful for demonstrating noise cancellation.

  • Bryton

    Multi channel support would be handy as well as the other comments.

  • Gabriel Smit

    sometimes multiple frequencies need to be generated – DON’t look for another app, just open multiple instances of this one and set each to the desired Hz, voila!…. make sure your equipment – which includes your ears and animals in the vicinity, can handle it!

  • Joe

    Please get rid of the volume slide rule and replace with either drop down or manual entry. It is practically impossible to get to a lower volume.

  • Ian Roberts

    I’ve found your website very helpful for ear training and getting my trumpet in tune – an on-going project.

    Also an on-going project: I’ve tried to convince friends to stop blindly trusting (deafly trusting?) their digital tuners by opening three browser windows, setting up a triad, tuning the third to sound nice and then demonstrating how out of tune the tuner reports that third. There’s life beyond equal temperament.

    My one tiny suggestion: drop the sound default sound level to maybe 25% to protect the hearing and/or sound equipment of unsuspecting users.

  • Ian Robert

    Another interesting observation you can make is to set a tone going through some stereo speakers and then move your head around the room and hear the nodes and anti-nodes.

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