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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

  • Chris Turner

    I used your fantastic app to test a power amp with an odd power supply issue.

    It worked very well.

    Thanks and Kudos.

  • Oystein Holter

    Great app!
    But do the different sine waves have the same volume? Some of them seem louder than others (in my ears, and with a Velleman db meter), and I wonder, is it just my speakers, or do the tones actually vary in volume.

  • Marxus

    Great tool for phreaking.

    You go sixes and i’ll go nines.

  • tom ralston

    Do you recommend or sell a speaker capable of outputting 40 hz? Especially one that can be attached to a PC. Even my stereo only speaker only goes down to 50hz. Just wondering, think you should sell one: -)

  • m

    hi mr s , this generator is amazing, i will show some support for your efforts. i have been working slofreggio tones. The octave shift is a great option. can you do binaural with this. i susspose if i open it up in 2 windows i could.
    Thanx for this great tool. wholeness and
    harmony friend

  • Dick Demaine

    Thank you!
    A great tool for trouble shooting PC sound systems. Lots of features and a very straight forward design

  • Dave

    Hi, it seems it would be nice to have the volume decreasing automatically with increasing pitch. I mean, some switch or some logarithmic correction value may make this still more usable. It is nice!

  • Jan

    Thanks for this tool.
    I tried the so-called Golden Ratio frequency at 1,618 Hz, but did not find it fascinating. Some apparently claim or think this frequency is liked by composers and listeners of (classical) music. On the other hand, the so-called Natural Frequency at 432 Hz and its lower and higher octaves sound agreeable.
    Best regards, Jan

  • Tobia

    Thanks for this tool.
    Using this site to test CI audibility ranges, balancing by tones and any other related issue.

  • Tobia

    Also, I suggest to add a list of preferred frequencies (I’d need to match those in CI mapping
    i.e. a list of 16 tones as: 333,455,540,642,762,906,…,6665Hz) and a “sweep option” between two given extremes within a certain time, to essay the frequency transition between electrodes (virtual and pure locations).
    Thanks very much again.

  • Paul

    Can this generator be used via pc to be used for chadnli experiment ? If so any ideas how to connect it up to the vibration generator?
    Many thanks

  • Guy

    Hello Mr. Szynalski,
    I just wanted to thank you for making your tone generator so accessible and easy to use. I also thought that I might tell you a little bit about what I’m using it for, if you would be interested. I am currently a senior in high school and for my final project, I am developing a solid-fuel turbojet, which incorporates the efficiency of a turbojet engine with the affordability of a solid-fuel rocket motor. I built and tested my first prototype a little over a week ago, and had purchased a laser tachometer in hopes that I could accurately record the rotation speed of the turbine. But unfortunately, smoke from the test interfered with the measurement and I was left with incomplete data. While analyzing the footage, I realized that the turbine created a very clearly discernible pitch. By matching the highest pitch with a specific frequency from your tone generator, and then dividing the frequency by the number of turbine blades, I was able to calculate how many rotations were in a second. (105, if you were curious) The visual footage and incomplete tachometer readings closely corroborated this figure, and I was able to document my results with fair certainty.

    Thanks again,

  • Bart

    I have tinnitus in my brain but can live with it.
    An extra problem I have now for 5 years is a (mechanical) tone of 107 Hz in my left ear.
    That tone is going away when other tones or noise is entering my left ear.

    Now I discovered this site and did some tests. When I set a tone of 62 or 63Hz in my left ear, the 107Hz tone is muted! But if the mechanical tone of 107 Hz is away, I hear the 63 Hz. Of course on some days, when I hear the 107 Hz permanent during Telework from home, I leave the 63 Hz running on my PC on a very low volume and it helps taking away that ugly 107Hz tone.


  • Michael

    I use this along with my bone shaker headphones to pollinate my tomatoes! 160hz seems to work ok.

  • K

    Hey! This is great but. Maybe you should put safety controls on this, so before playing a subsonic (supersonic too) frequency it gives you a warning message or denied action to keep our organs safe… Maybe you have this, but I’m not pressing play to find out. Forgive me if I’m wrong.

  • B

    You should accept BAT crypto currency donations from Brave browser users!

  • bean

    i played this during class on a little less than full volume and the reactions were funny. Its also so cool to hear all the different hertz. I liked this

  • Emily Stone


    I am using this tone generator for an independent research project in college. Do you happen to know if this website has any error associated with it? I am required to make note of possible measurement error in the instruments I use. For example, if I play a tone at 200Hz, is there a possibility of it playing at 200Hz +/- 0.01 Hz?

    Thank you!

  • Steve

    Per this article entitled “Strong humming for one hour daily to terminate chronic rhinosinusitis in four days: a case report and hypothesis for action by stimulation of endogenous nasal nitric oxide production”

    “This case report shows that a subject hummed strongly at a low pitch ( approximately 130 Hz) for 1h (18 hums per minute) at bedtime the first night, and hummed 60-120 times 4 times a day for the following 4 days as treatment for severe CRS.”

    this site helped me hear what 130 Hz sounds like so I could match it to benefit from this treatment.

  • Quarinteen

    Anyone else opening portals with this tool?

  • Pierre Edouard Morin

    I am sensitive to EMF from electronic equipments,
    I use a mini pocket radio receiver to make the vibration audible.
    Then I go to your application for tone generation and match the frequency.
    Having a frequqency number, I can research the source of the vibration and find the component inside the circuit that emits.
    The goal is to try different circuitry with least noise…
    Thank you Tomasz, Great tool to use.
    Pierre Edouard

  • Mark Hinman

    I think it should be noted that the MIT Alzheimer’s study of 40 HZ used a saw tooth wave; not a sine wave. There’s a link below. I think this makes a difference, as the saw tooth wave more closely resembles the actual brain wave.

  • Mutant Buzzard

    This is too cool, thanks!

  • Matt Garrett

    Great online app! Thank you so much. I use it to tune and diag a quad amp very high powered pa system in a large building using a vintage jbl paragon as the center focus reproducer. Really helpful in finding the strong and weak points of the different complements and bringing it all together especially around crossover freqs. Also great for finding resonance rattles. Those mid 50hz ranges really are tough, from plate glass windows 90ft away rattling to the equip itself. It also reminds me im simply deaf above 11k hz 🙂

  • Tom

    How can I make an mp3 file of a tone?

  • Bruce Ratcliffe

    We all start out life with no anger at being done wrong by the myriad that learn to do so as they grow. You are one of those rare individuals who SOMEHOW, in spite of all the times mean-spirited people have taken advantage of your innate kindness, have continue on your path through life with trust and generosity being your guiding lights. I just stumbled onto your website, and will use it to teach my physics classes forthwith. I’ll probably use it for all of 10 minutes, but my donation is not based upon how much use I will get out of it; rather, it is based on my admiration for how admirable you–and your efforts to create a useful tool, both for teachers, and audio engineers, and their ilk–are.

  • CXavier

    usefull for annoying the bullys at school 10/10 would do again

  • Bruce

    I love this online App, I use it whenever I need to hear what a specific frequency sounds like, in my research. Many thanks, I will be funding a little when next I have some money. I don’t expect something for nothing.

  • Avis Hickman-Gibb

    My highest frequency was 11,123 Hz. Not sure what to do with information. I was a little sad, when tested in Physics class when at school I was the only one who could hear 20,000 Hz. But time gets us all!

    I found the 40 Hz very comforting. Nit sure what to do with that information, either

  • ben

    it’s possible to add option that can play two different frequency at same time? for example 440hz 45hz ?

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