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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

  • cs127

    Only sine waves?

  • Leonard Rath


    You are a good person.
    I’ll donate 5$ via paypal, thanks for your effort for all of us 🙂


  • Alfred Lacazette

    I see sharp versions of notes on the list but what about flats? This would be hugely more useful if the user could specify the note in normal musical notation, or if you had that on the list. I’m not musical myself so I need it simple. Which is Middle C? Which is is E flat?

    • Tomasz P. Szynalski

      The notes are specified in normal musical notation. E flat is the same as D sharp. Middle C is C4. I’ve added a more extensive description of each note — you can mouse over a button to see it.

  • wilma

    i had loads of fun annoying the teachers in class with this!

  • Aris

    Thank you Tomasz for this tool!
    I have a tinnitus which consist of many frequencies, as your tool helped me to realize, starting from about 6.000 to 12.000+. The most annoying are the high frequencies. Sadly I realized that I can’t hear anything above 12.000 – 12.500Hz. The interesting thing is that the “annoying” infrequence looks like it sounds “higher” then the last one I can hear (12.500) :0
    One thing I wanted to ask you: am I supposed to hear the sounds your tool generates under the 20Hz? I ask because I can hear very clear even the 1Hz which sounds like a heart beating!

    • Tomasz P. Szynalski

      Hi Aris,
      Nobody can hear 1 Hz. What you may hear is higher harmonic frequencies (distortion) generated by your speakers as they struggle to play that sound.
      In general, sounds below Hz are more “felt” than heard.

  • Martin Andersen

    What is the accuracy of your tone generator? Can I use it test the accuracy of my chromatic tuning machines and apps? (I am a professional violist and violinist.)
    Thank you!
    Martin Andersen

  • quinn

    Hi. Love the Tone Generator. I am trying to understand tone and Hz a bit better. I see lots of music advertised on YouTube that is a 432Hz, or 528Hz, which are, apparently, very therapeutic frequencies.
    How can you have music at a specific tone? A tone at just one frequency, is just that, a monotonous tone.
    Are they embedding that tone, under the music??

  • XA

    Hi I just noticed on Windows 10 Chrome I am using studio monitors to listen to sine waves and I can say the wave produced for example when I listen to 50 Hz is definitely not a sine wave when volume is set to 100%. When I reduce the volume the problem is resolved. I’m not sure why it would be clipping or any other problem but I have tried with multiple sources, headphones straight from motherboard, amp/monitors, and the effect is the same. To compare I tried another website’s tone generator and 50 Hz was produced without other frequencies. I used a spectrum analyzer and the buzz produced when listening to your tone gen is of around 120 Hz when listening to a 50 Hz sine wave. This problem is mitigated when lowering the volume on the tone generator, it’s not affected by the volume of the amplifier or any other source as I tried. Just thought I’d mention.

  • Robert Blackham

    I am experimenting with “noise cancelling” headphones, to see what frequency range they work best.
    One characteristic I notice about Tone Generator is that when I raise frequency, the sound output from my speakers rises (I am using an old Dell XPS laptop). It isn’t just my perception, I have a sound meter alongside. I can e-mail a table of the measured dB against Hz readings if you want.
    Anyway my question is, can there be a setting that automatically adjusts volume of the Tone Generator output to constant dB (subject to the quality of the user’s speaker system) ?
    I am not expert in audio equipment, I guess there may be other issues involved with this idea.

    • Tomasz P. Szynalski

      Hi Robert,
      There’s too many unknown variables. The frequency response depends on the speakers, the acoustics of the room and your listening position.
      You can flatten the curve somehow using a technique called “room correction”, where you measure the full range of frequences using a measurement microphone, and then apply equalizer settings that boost some frequencies and attenuate others. But even that process does not produce a perfectly flat response.

  • Bob

    I think my ringing in my right ear is around 5,500 to 6,000. Is there a way I can listen to a frequency to neutralize it? I don’t understand 1/2x or 2x, what that does. I’ve heard that there is a frequency that cancels other frequencies? Have a hard time sleeping with this? Any suggestions would be greatly appreciated.

  • win grace

    why does the tone lower with greater loudness

  • Matvey


    Can you add input of user value by clicking on a frequency?

  • Ugur

    Hi Tomasz,

    Thank you very much for this very useful website. I was wondering though: Can we go to higher frequencies? I have a piezo based speaker (this one:, and I want to test it at high frequencies. I am not sure how to connect it to my computer though, but I will give it a try.

    • Tomasz P. Szynalski

      I’m not sure if the DAC in your audio card will make sounds above 24 kHz (even if it supports a sample rate of 96 kHz). I’ve done some research on the Web and can’t find any confirmation. If you manage to get it working, let me know.

  • K

    I’m a musician, and I use this almost every day to practice long tones over a pure frequency, to create the harmonics with my instrument and improve tone, breath control, and intonation. Great site!

  • ProDigit

    Great link!

    Could you program in the website a saw wave, and blockwave, to be able to hear lower frequencies supported by my pc speaker better?
    The sine wave is very hard to hear at frequencies below 250Hz on my pc.

  • carol Keeffe

    Hello Tom,

    Are you familiar with the zapper ( and also (a form of a Rife machine) and how these devices heal people because the frequencies kill parasites. One tremendous outcome in particular is the curing of people who have been suffering terribly from Lyme disease. I am thrilled that your tone generator may be so much easier to use than other devices. Have you experimented with this? I have a friend who hasn’t been able to move any part of her body except her head for over a decade because of Lyme disease . . . your generator gives me hope for her! Thank you for dedication and for applying your talent and gifts to help us all. Carol

    • Tomasz P. Szynalski

      Hi Carol,
      I took a quick look and these are electrical generators; mine is a sound generator. Very different things, although both can have a frequency. By the way, I feel duty-bound to note that those devices are totally pseudoscientific and I’m afraid will certainly do nothing for your friends Lyme disease (my sympathies BTW). Best wishes to you and your friend.

  • greg

    can i make a cd of a tone or different tones

  • Jane

    Awesome site! Is it possible to listen to my tone of 5500hz for one hour?? Great relief for my severe tinnitus.

  • pougiyft

    I can even listen to the sound with frequency less 20 Hz with earphones.
    How is this even possible.

  • guy russo

    Great site, one request:

    Could you please make a box to type in the exact number to generate that frequency?

  • Kristo

    Great tool, thank you for it! Would only kindly ask for a phase switch for one of the channels and it would also be even more perfect if there was a “play” but that would start the sweep from bottom to the top in a logaritmic way, so that user could freely set a time say 30 seconds and by that time the generator would auto-sweep from 20hz to 20khz

  • Mark

    Thanks for creating such a simple to use, elegant program. With this I quickly and easily identified the predominant frequency of my tinnitus and will use it along with stimulation the vagus nerve (through slow breathing) to see if the brain can be “rebooted” & minimize the volume of tinnitus. Your directions are clear and easy to understand as well. I’d rate this online-tone-generator at an A+ !

  • KRS

    Yes, the email address is real, and so is my tinnitus which I have had for almost exactly 22 years now.

    About 24 hours ago I had a sudden increase in the “perceived” volume of my tinnitus, in the same ear (right) that it started with on a Saturday afternoon in September 1995.

    I was a communications systems technician (air force), so I am familiar with not only radio, but also auditory frequencies. As a tech, I had access to tone generators, but I left the military decades ago, so I found your tone generator.

    Here is what your app has told me. My left ear is working perfectly (for someone my age), but my right can only hear 300Hz and below at NORMAL volume.

    A crazy thing happens at 600 Hz and above at much higher volume. In my right ear I hear a higher harmonic, like 8x or 16x higher! I have to remove my Sennheiser HD202 headphones from my left ear when doing this, for obvious reasons.

    A very useful diagnostic tool. Thank You.

  • Clint

    Earlier someone requested the ability to simultaneously play two frequencies. I just did that using Firefox55.0.3 by opening two windows. Every function works independently, and my crummy speakers respond as best they can.

  • Stephen

    Fantastic Piece of Software!

    Request to input sound volume.
    Slider too hard to adjust exactly.

    Much Appreciated,

    Try 432 in all octaves ……… srk

  • robert

    Hi Thomas,

    Did you ever seen the video that someone used your tone genarator to open black holes to other dimensions? haha

    • Tomasz P. Szynalski

      Hi Robert,
      Although such phenomena have been reported by a small number of users, please note that opening tears in timespace is an unsupported feature. Please exercise caution and limit yourself to peeking. Do not enter the tear under any circumstances.

      Sedona, AZ

  • Glazzsherlock

    Your site seems to be non functioning. I am on a Samsung smartphone connected to a Bluetooth speaker. Model 808. I don’t understand?

  • Glazzsherlock

    Is your site down. Really frustrating trying to use something that doesn’t function.

  • GeeEaZy

    i’m exploring war on robocallers. i believe that a frequency of about 170 Hz has a good chance of matching the harmonic of the ic boards in their gobocall box. if i can send them that frequency of sufficient strength and duration, i could cause fatigue in the solder joints of components; resulting in equipment failure. am i waisting my time thinking of this? – has anyone done it? – is it legal?

  • panpan

    i just use this to piss other kids off cause only they can hear it and not the teachers

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