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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 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)
  • 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.


179 Comments so far ↓

  • Jorge

    That’s why I love this blog: Tom always posts something cool. Thanks Tom!

  • Čech

    It’s bad luck for me. I use linux. 😀 grrr But it’s good toy. Nice one.

  • Čech

    So I try it in Ubuntu 12.04 with firefox 15.0 and it works propably bad. I listen good 20hz to 20173hz. Is it this bug? Does it give bad sound?

  • hunterz0

    It’s not working for me in Firefox 18 under Windows 7. The controls are there (minus the frequency number), but I can’t interact with them.

    • Tomasz

      Thanks, fixed. There was a syntax error in the JS — I don’t know how I managed to upload a non-functional file — I always test my sites after I upload them to the server.

      Physics will never explain things like this.

  • John

    Have you thought of giving users the option to change the phase of the signal so that they could possibly reduce or cancel the sound from another device. I have tinnitus and would like to see if it is possible to use this method to reduce the level of the sound in my head.

  • Tomik

    It works in Ubuntu 12.04 with Firefox 25.
    Nice job, thanks!

  • charlesdschultz

    Agreed, good stuff – very nice presentation, simple and easy-to-use.

    One request. Can you allow frequencies lower than 20Hz? I realize that drops below human hearing, but in terms of science, it makes for great woofer visuals.

    Along that line, have you considered having multiple simultaneous tone generators? Most of the sounds we hear (especially voice) are made of multiple frequencies. I would love to demonstrate to a class how sin waves destructively and constructively react to each other.

    Keep up the good work!

    • Tomasz

      I’ve modified the scale to allow frequencies starting from 1 Hz.
      I imagine demonstrating constructive and destructive interference would take some thought to do right. You’d have to make it possible to manipulate the phase. Perhaps you could do your demonstration with Audacity?

      • Charles

        Tomasz, that totally rocks – thanks for the quick turn around. So even though I cannot hear the actual frequency, I can hear the physical movement of the cone even down to 10Hz. Kinda cool. 🙂

  • Andrew

    Best sound application EVER !!! Thanks!

  • James

    nice app. My wife is using it right now for her sinus infection. She is pressing a speaker into her cheek + eyebrow. Somewhere between 100-107hz seems to be the best to break up her mucous. We’ve read elsewhere that people do this and it clears up the sinus infection immediately. Fingers crossed.

  • Rev. Dragon's Eye

    Nice and handy!

    Definitely works with FireFox v31.0 on Manjaro Linux installation.

    Would love to see how one can balance the volume based on the frequency as the higher frequencies often are louder than the lower frequencies. (Has to do with the lower losses of energy and shorter wavelengths.) – I used to know how to automatically adjust the volume via software (much like a compressor/compander would do in a circuit).


    I have made sure to bookmark this on the other part of the site. Seems that the saved-as-complete page also works well (for a locally-stored copy).

    Great idea.

    – Rev. Dragon’s Eye

  • Tony.

    What about also displaying the pitch note for example A= 440 B= C= so on and so on. just the frequency is not enough. I have to keep searching for one of those now. by/

  • Steve A

    This is a great tool. Is there a way to get the frequencies to a a couple of decimal places? I have been using it to tune the banjo, but it is hard to get the perfect frequency…. But then again, as they say, you can tune a Harley better than you can tune a banjo.

  • lukephills

    Hi Tomasz, this is a great tool – nice work! I have a web audio question for you… What is the difference between Firefox and Chrome when it comes to changing oscillator frequency. Have you noticed that if you slide quickly in firefox the frequency-change isn’t smooth like it is in Chrome or Safari.

    I’ve been trying to fix something I made a while ago which doesn’t work properly on Firefox for that reason (

    Any help would be much appreciated. Thanks!

  • Pretty-deaf Dave

    I was just now looking for a tone generator to test my hearing in a ~deaf ear and had imagined something like this one with a slider….and lo and behold, here it is and elegantly and simply implemented!! Thanks so much. This is a wonderful tool, and it turns out I can hear with that ear within a narrow range. Good to know this.

  • EPeterson

    I’ve been looking for a tone generator with a slider just like this to teach about tuning musical instruments. This is elegantly done, thank you!

  • EPeterson

    OK, now I’m getting more ideas! Can a volume control be added to this online tone generator? (I have no idea how hard that might be) So far I can open a couple of browser windows and play them at the same time to demonstrate intonation and beats, but I’d also really like to open several browser windows and set them to different overtones on the same fundamental, and adjust the volume so the fundamental is louder than its overtones… but then adjust the volume of different overtones to demonstrate what (for example) a clarinettist should be listening for in a rich, centered sound.

  • Keith

    Thanks – I really appreciate this thing.

  • Jalim

    Just wanted to drop in and leave a word of thanks. I’m a science teacher and I’ve been using this online application for three years now to help with my unit on sound. It is EXACTLY what I needed to do some of our experiments. Thank you!

  • Termite

    Thanks for this – I’ve had tinnitus for a while, recently after snorkling and diving, my right ear is really bad. But I am struggling to find the frequency. When using it I do find that some frequencies I can’t actually hear as I scroll through – not sure if that is related? Anyway – thanks again for the tool even while I’m still trying to find my frequency 🙂

  • Brian Beckmann

    Thanks for making this, I use it to localize the ‘hum’ I hear; it was consistently 66Hz but now varies between 59 and 72. At least I know it’ real now.

  • Zman

    Well done, thank you. Works in Opera 26.0 as well.

    Suggestion: I think would be better to make buttons (or single button) with changing color when generation is active. Right now if you click PLAY and you can not hear the sound (i.e. when the frequency is too low or too high to work on particular speakers) – there is no way to tell if generator is OFF or ON. This is quite confusing if you want to test working frequency range of output.

    • Tomasz

      Good point! I’ve replaced the two separate Play and Stop buttons with one button that changes from Play to Stop when you press Play.

  • loren

    thank you, this is great for working on my tube amp…I have no idea what’s different about yours but according to my scope yours is the only one of 5 or so I tried that has true, clean, sine waves. Thanx again!

    • Tomasz

      Oh, it’s nothing special. Every night, I polish the sine waves with a special paste until they’re completely smooth.

      • astrodoug

        Hi Tomasz. Your sound generator is fantastic. So much so that I want to download it onto my computer to do some experiments. I am happy to pay for it if I could get it onto a couple of pc’s and get to work so I can save the HZ combinations

  • Parsifal

    Bardzo porzadny generator, prosty w uzyciu i praktyczny. Przynajmniej mozna powoli i dokladnie sprawdzic to, co sie chce sprawdzic. Pozdrawiam.

  • Greg

    Tomasz — best frequency-to-tone generator site I have come across! Love the frequency slider. First, a couple of MINOR improvement requests (I hope). Can the up-down frequency adjustment arrows be interactive so that single clicking makes a 1 Hz change, but holding the arrow down with the mouse makes multiple 1Hz changes (until you stop pressing on it with the mouse)? That would permit the desired frequency to be selected much faster — especially important in the higher ranges. Also, can you make the word “PLAY” green and the word “STOP” red — when you drag the slider to far too the right and the volume is blasting and numbing the brain, colors help guide one to the STOP button quickly. Also, can you tell us what Wave the tone represents? Better yet, can we select the Wave, ie. Sawtooth-Sine-Square-Triangle? Also, once you select a frequency, can the music note change instantly to match — for simplicity of presentation, I suggest dropping the Hz after the music note and just putting a “+” or “-” after the Hz to let the person know the selected frequency is a bit higher/lower than the music note indicated — if curious, the person could always adjust the frequency up/down until the “+/-” went away, indicating the frequency was now within 1Hz of the music note shown. Second, a MAJOR improvement request. Rather than have the frequency only play a wave tone, can it also play the closest piano note? I am working with some healers who prefer to discern the healing tone as a frequency, yet we want to play music notes to the person being healed (much easier to listen to). If you do even a fraction of all this, that would be great !! Your work on this sound tool is very much appreciated !!

  • Tom S

    My tinnitus rings right at 3907 HZ. Interesting. Thanks.

  • Gary

    This is a really well designed tool. Any chance of obtaining a download which does not require being online to use it?

  • Dan

    I want to use something like this to tune my sliders of different frequencies on my equalizer. Do you make a CD that I can play in my system to do that?

  • Dets

    Great tool. I used it to determine the feedback frequency of a live recording, so I could set a extremely small bandwidth equalizer to remove the noise. Thanks very much,

  • Denka

    I would love to see an option to select a frequency for the right ear and a different frequency for the left ear even using a separate tab. Then it would be possible to try bin-aural beat experiments. Thanks fro such a wonderful and simple tool.

  • Mark

    Would be improved if the left & right arrow keys controlled the lowering and raising of frequencies.

  • Leah

    Your tone generatort is the best I have seen. Would you consider repalcing the drop down menu for selecting a note, by a picture of a piano keyboard, that could be clicked on to select a note. I recently retired from Java programming, and it has been about 10 years since I hav done any web design, so I have no idea how hard this would be. If you are interested in the idea, I would love to help with any grunt needed.

    • Tomasz

      Thanks for the idea. I’ve given it some thought and while a piano keyboard would definitely look better, I can’t think of any functional benefits. In fact, one disadvantage would be that piano keys are quite narrow and it would be difficult to fit the frequency (e.g. “1760 Hz”) on the key. Did you have any particular use cases in mind?

  • Paul T

    Hi Tomasz,
    Thanks for the tone generator. I have used it to investigate the ideas in Ross W Duffin’s book “How Equal Temperament Ruined Harmony” – about the Equal Temperament system now almost universally used in tuning musical instruments, but which mostly does not correspond to mathematically (therefore harmonically) correct frequency ratios for chords.
    (The tip about opening the generator in several browser tabs was key for this!)
    With the tone generator it is easy to hear that the Eq Temp. A major chord (using A440, C#554.36, E659.25) is very different from the pure harmony of the triad played with 440/550/660.

  • Derek Rayburn

    Great Tone Generator. Was looking for something to generate low frequencies to drive away carpenter bees when the tone was amplified through large speakers mounted to my carport but low enough for my neighbors not to notice… this works! It also helped me identify my Tinnitus frequency; 4382hz! I found the freq my dog hates. I found what my laptop speakers are capable of reproducing (not much) and what my wife hates so badly she kept her fingers in her ears. This could be the most useful of my discoveries. However, ironically its the frequency that matches my tinnitus so its just as aggravating to me. I do believe these sine waves are better because Tom polishes them nightly with a special paste. This page has earned a rare bookmark from me!

    • Tomasz

      Derek, many thanks for the report. I’m glad you’ve put my creation to so many productive uses. Off to get my polishing paste…

      P.S. Did you find the special easter-egg frequency that makes you think you are a moose? That one’s fun.

  • Or dobkowski

    well done, thanks
    What kind of tuning did you use?
    Because the lower octaves sounded offtune to me….. 🙂
    (A2-B2-C3 sounds weird, to my ear the B2 is too low for example)
    It’s intresting if there is a mistake in frequncies, or is it that the ET tuning is more notcible at such low notes

    • Tomasz

      The frequencies are calculated according to the formula for Equal Temperament (12-TET). For example, B2 is about 123.471 Hz. The frequency is listed next to the note, so you can check for yourself.

      • David Lewis

        Very promising tool BUT read on… I am looking for software which will play frequencies accurately so I can hear Byzantine chant scales – which are quite different from modern western major or minor scales. I was therefore very disappointed to find that doubling the frequency (e.g. A4 at 440 to A5 at 880) does not raise the played note by one octave, but only by about a major 7th. This seems to happen with all frequencies over C4, but C4 itself to C5 sounded OK. I am a lifelong professional singer and choir director with a very accurate ear – it needs to be! This problem, I’m afraid, renders your tool completely useless. Sorry!

  • Simon

    I liked it a lot maybe one day youll have it setup so that we can download a short sample a few seconds of a whatever tone were looking for huh

  • Markus

    Works nicely! I could hear sounds from around 45~17.600Hz being 20 years old.

  • paki

    I don’t know what tinitus means and why you have made up all this effort, but your tone generator is VERY VERY addictive. I have already spent 2 hours sliding the bar and listening to tones.

  • Dave

    Can I use your tone generator to show people what 50 DB sounds like?

  • Taei Zunnie

    Just wanted to say thanks for a “Great Audio Tool”!

  • elvear

    I just wanted to say thank you! I am using this tool to improve my intonation on the violin by playing a tone based on the key I’m practicing in. It’s a wonderful tool. Again, thank you!

  • Janice Wang

    Hi Tom, we would like to include your online tone generator in an experiment where we will ask people match the taste of food/drinks to a frequency. Would it be possible to embed it in an online survey platform in some way? Thank you!!

    • Tomasz

      Hi Janice. It should be possible to load it in an IFRAME. I understand you’re talking about noncommercial use?

      • Janice

        Yes it’s for an academic study, my PhD topic is the interaction between sound and taste. Would it also be possible to make some modifications to the range of frequencies generated? Please free feel to email me offline as well. Thank you!

  • Jay Johnston

    I wanted to let you know I am using this for Resonant Voice Therapy (used for treating hoarseness). This is the simplest most direct tool I’ve seen to help me get the right pitch. Thanks.

  • joe Sockit

    Most excellent Tomaz! I was about to buy a program to tune my sound system just to get the tone generator function since I have the DB measuring equipment. it didn’t occur to look online as I didn’t think anyone would post something this useful for free. I have been using one of my active crossovers to tune the passive crossovers I built for some mains. Now I can dial in exactly where I need to be component wise to get 1850hz as a Xover point for the horn drivers. Now, to compensate for the impedance changes!!. Thank you!!. I put out CD’s of local bands I do sound for (one CD a month). Tell me what type of music you like and I’ll send you some selections as a thank you for your most useful tool. Shortsville Sound.

  • joe Sockit

    All you youngsters, measure your hearing now and archive it somewhere.
    See where you are in 25-30 years. I’m an old musician and years of standing next to crash cymbals and screaming Marshall amps has my high end down to about 15k, and that is straining. Take care of your hearing my friends!

  • Chris Mel.

    Used it to test DIY led color organ. Thank you very much, job well done!

  • Tomasz

    I’ve just published an updated version of the generator. Here are the most important changes:

    – Added visual “playing” indicator to warn against sudden jumps in volume when you change frequencies
    – Added octave up/down buttons (frequency ×2 and /2)
    – Keyboard shortcuts: Spacebar toggles Play/Stop, Left/Right arrows change frequency (even if slider is not highlighted), Shift+Left/Right fine-tunes frequency by 1 Hz
    – Continued press on button keeps changing the frequency (no longer have to click on Left/Right buttons repeatedly)
    – Adapted to mobile devices – works on iOS and Android (Chrome).
    – Visual tweaks (e.g. retina-resolution images)

  • Jim McKenna

    Simply fabulous!..I restore & repair vintage synthesizers & use Tomasz’ Tone Generator at least twice a day, every day to calibrate them..Many thanks!

  • Greg

    I needed a constant tone to test a flaky VOIP phone connection and this worked great. Thanks!

  • Dirk

    Hey tom 🙂 Very nice tool and it works for me flawlessly 🙂
    The only thing I would like to see added is the ability to phase shift. 180 degrees would serve my purpose 🙂 I have no clue how hard that would be but if it was a simple thing, it would add alot for me 🙂

  • Christina Gabriel

    Thank you! I just got a basic audiogram as the first step toward understanding the tinnitus (+ weird tone at around 1KHz that I hear when I shake my head) that I started to get about a year ago. Your tone generator is an excellent tool for me to understand and validate what the audiologist measured. Now I can see just where my hearing begins to fall off in each ear and then roughly match the tinnitus frequency. I like having a quantitative measurement and I hope this also will help me give the clearest possible description of my symptoms to the specialists for the next steps toward diagnosis and (with luck) treatment. I do recognize that there may be no way to get rid of this, but it’s still helpful to be able to characterize it for myself. Something fun to do to balance being annoyed by the tinnitus!

  • userbarna

    Great great tool! Congratulations for building it! A real example of useful web apps, I found it while looking for exaclty what it does. You can train your ears to learn and recognize frequencies, the words of music! Thank you very much! Regards from Spain

  • cambieroilmondo

    Very nice 🙂
    thanks for that, I used it today in order to test a simple audio frequencymeter!

  • DreamMaster Pro

    This program is an example of perfection, pure sine wave with amplitude that fades up at the start and down at the end.

    I used it to find the frequency of a random (and unwanted) tone that lasts about 1/2 second, occasionally coming from the Atmega1284p processor I’m programming. I now know it’s 291 Hz. Hopefully that will help me locate the source and cause.

    • userbarna

      Lol! I did the same trying to match up to a neigbour vacuum cleaner motor and I remember it was something like five hundred and something Hz. Great great tool! It’d be nice to have a way of training all the notes within an octave, to start, at least, recognizing which frequency belongs to which piano frequency. What do you think?

      • userbarna

        Sorry, I wanted to write “to which piano octave”

      • DreamMaster Pro

        For matching up to piano frequencies, open this tool in another tab at the same time:

        • userbarna

          Very interesting! Now I have a crucial question: I remember watching a Youtube video talking about the difficulties of tunning a piano and the Well Tempered Clavier… So, this is one more thing that I love about this page, the fact that what you hear are pure tones, pure frequencies, aren’t they?

          So this brings to my mind the question of … as you said, If I start using virtualpiano and train my ear to recognize C4 for instance… Would I be listening to the same tone coming from a piano and other from a guitar for instance? Or do they have little differences in its frequency number? Like 262 (C4) and maybe in the guitar I get 264 or sth?

          Great app and page who has also gathered we people that love pure frequencies, everything is a frequency!

          • DreamMaster Pro

            The frequency would remain the same, no matter what instrument you played it on. For example, A 440 is always A 440 (if correctly tuned). What changes is the other frequencies generated along with it, telling your ear the note is coming from a piano, or a guitar.

            The tempered scale is a compromise, because A-sharp and B-flat (for example) are not quite the same note, yet there is only one piano key to press for both of them. This is why people singing in harmony with no instruments at all can be so amazingly beautiful. It is because they can sing the actual true notes without any tempering at all.

  • Rennie

    It’s excellent for testing out resonant room modes. My current speakers and room love 50-60Hz and man does it resonate there XD

  • Mike

    This is a great tool, thanks for hosting it. Is there any chance you could add a balance slider? I have tinnitus but mostly in my left ear. I do not want to change the settings in Windows because I would like to listen to music at the same time I listen to the tone from your site. Any chance you could add that? And while I am asking, any chance you could add the ability to play more than one tone at a time?

  • Chanayvonne

    Thank you, your efforts are appreciated.

    • CypressTheCorruptOne

      I used this for my science project, it helped a lot! Thanks for your effort!
      However, my head always hurts after..But, that’s the price you must pay for science!

  • Mark

    I just used this wonderful app for a ‘dancing oobleck’ experiment in my science class at uni. I can’t wait to do it with the students when I am teaching primary school. Thanks Tomasz.

  • Steve Rutkowski

    I’ll be using this tone generator for the same reason that was posted last year by ‘Loren’. The only difference is that he was working on tube amps, and I’ll be troubleshooting solid state.
    I bought an older dual trace Tektronix scope yesterday and needed a way to generate a known signal to test it. This app worked perfectly and showed me that I had a fully functional T912 scope with two 10X probes (with all attachments) a scope cover, a Tektronix K212 cart, and all manuals for $50!!

  • Milk Brewster

    Having the parameters selected in the url, with the url updated when the interface is, would allow tabs to reopen with what was set in the last browsing session.

  • Sandy

    Would like to use your tone generator for an experiment with my students. Your volume adjustment is in %. Do you know the decibels of the volume?

    • mclainde

      The decibel is a measure of sound pressure, I think. (If someone knows better, please correct me!) So the volume of the source content (tone generator) cannot be given in decibels, since you are going to play it back through a headphone or speaker or amplifier and speaker combo that will all generate different levels of sound pressure. For instance, you can plug your phone into an amp and generate 110 decibels to fill a stadium, or you can plug it into a mini speaker and produce 20 or 30 decibels.

  • Jos

    By using the FFT with MATLAB i get 880Hz for 440 Hz, why?

  • Conrad

    Just used this great tool to match at which hertz my right ear was temporarily ringing. ~733Hz, it seems.

  • chris wilson

    this is exactly what i was looking for. i just suffered an ear infection and as a result acquired 2 ruptured eardrums. this ringing is getting more and more annoying but i at least wanted to know the frequencies i was hearing. mine are 400 and 4000 hz. it varies as to which one is dominant. its easier to tolerate just knowing the frequencies.

  • Edward

    Simple and useful. Thanks. A suggestion: It would be nice to be able to link to a particular frequency, e.g., and possibly also have a “Copy link” button like you get on e.g. to be able to obtain the link easily. Thanks again.

  • Dave McKenzie

    I was turned onto this generator, to see if I could identify the frequency of my tinnitus ringing. In no time, I found that it was approx. 6,000Hz. I haven’t resolved anything yet, but it’s nice knowing that I was able to put a number to it. I have “always” had this condition (loud noises from childhood on); maybe I’m on the road to a therapy…like re-training with white noise. Anyway, pretty cool.

    • Bob

      Yes, I also have tinnitus around that 6K+ range. The problem is that while I cancel out the sound, it drives everyone else in the room nuts. I guess I have to use headphones.

      • dj6040

        FYI, I have had tinnitus for a long time and I found that the amount of salt I consume has a great effect on it. By limiting the salt intake I have reduced the ringing to where I am hardly aware of it. The other thing is ear protection from loud noises. For example, if I use my circular saw to cut a piece of wood and forget the ear plugs, my ears will ring loudly for about 8 hours. I’ll where my plugs at movies, concerts, etc., anywhere I might encounter loud sounds.

  • Francesca Miller

    I can’t get dual tones to stop! Otherwise, a brilliant device. Please respond asap as I don’t know what this will do to my phone.
    Thanks so much.

  • Gian Cosani

    hello is this in 440hz tuned? or 432hz? i do like this generator but im just curious when you made the intial set up was it tuned 440 or 432

  • dj6040

    Thanks this is what I have been looking for. Many tone generators out there but this is the only one I have found that provides the related musical notations.
    I wish you would make this a regular program so I can run it on my PC when I am offline.

    • Steve Rutkowski

      Your message piqued my interest..
      I use the tone generator in conjunction with an oscilloscope to troubleshoot guitar amplifiers. If I use it with my desktop there’s a 60 cycle hum that tags along. This normally doesn’t affect my troubleshooting, but it occasionally gets irritating, so I use it with my laptop, which doesn’t have this problem.

      Anyway, just for giggles, I went to the generator page today (using Firefox on my laptop) and did a “File -> Save Page As”. Then I shut down Firefox, disconnected the laptop from my network, and fired up the saved page offline.

      It worked ‘almost’ perfectly! I say ‘almost’ because the left/right arrows that decrease/increase the tone by a single Hz were hidden. You can still find them by moving your cursor around the areas where they should be until your cursor changes, so it’s really not a problem.

      • dj6040

        Thanks for the suggestion I will try that. I use it to tune each of my drums to a specific pitch. It really helps to have a constant tone playing that I can match up with.

  • Lonny

    Thanks for this tone gen. very helpful to us HAMS for radio testing

  • Avimun

    Great application indeed. I am just wondering a bit how sounds with ‘f’ less than 20Hz is actually being audible …. Is the correspondence between the f (<20Hz) and the tone is accurate !!!

  • Joseph Vernice

    I am using your tome generator to test the response of my hearing aids. The hearing aids have frequency compression since I have no response about 2kHz. It divides frequencies by two (down an octave) so I can hear frequencies above 2kHz (and less than 4kHz). My HA’s can be tweaked as needed using this tool.

  • M.Anthony

    I am using Safari with an ipadii and I can not get the note menue to work. Any advice? Thanks, great generator!

  • gciriani

    Very interesting. I actually am able to measure interference zones. By moving my head left to right, the two stereo loudspeakers in my PC sum or subtract each other.

  • Loek van der Heide

    HI there, Mr./Madam,
    I Thank you very much getting me a tone generator which I can use as piano-tuner.
    I am also [“voorstander”NL] ‘in favour of’ lowering the diapason of all opera orchestra’s beeing producing opera’s from 1800-1900 Till Verdi & Puccini
    This, of course, Verdi’s Plead for lowering the a’ diapason to 432 Hz in 1881
    by then since 1842 by French decrete rised to 440 Hz……
    This goes also for the re-introduction of
    – Period instruments Rossini /Verdi/Puccini opera’s
    – 3-stringed Contrabasses ‘Scordatura’ also tuned to CC on lowest string
    – gut- stringed all strings except Contrabasses’ lowest CC/EE
    This feature is also good, tuning lowest 32′ / 64′ (resultante) and Octo- CCC tone of octo-sub-contrabass violone, to be used in [ondermeer] Verdi’s Otello and also ‘Il Re Lear’ sounding of Storms. (Re lear is a new composition which I am proceed tot complete…..)

  • Jason

    Would it be possible to include a toggle switch that enables an “Equal loudness” mode? This is by far my preferred online generator, and has been very useful for me, thank you!

    • Tomasz

      Hi Jason. It would be impossible to ensure equal loudness without knowing the frequency response of your speaker. Also, equal loudness over what range? You can’t make a 20 Hz sound be as loud as a 2 kHz sound without making the 2 kHz sound very quiet.

      • Jason

        To be sure what happens on the users end would be affected by speaker/headphone response, but if the slider adjusted volume to somewhat closely follow ISO226 and assumes a perfectly flat speaker response i think it would be extremely useful for very roughly determining the flatness/bass response of ones speaker/headphones and room response without requiring a pricey calibrated mic and software purchase. I understand many frequencies would be quieter to avoid signal clipping, but testing for speakers/headphones by ear, especially at low volumes, I believe it would be very useful. As it stands I was only able to find a wav file from audiocheck for a “perceptual” sine sweep with all of my googling. Comparing it to a normal sine sweep shows a massive difference in perceived volumes depending on frequency. It was extremely helpful for how limited its control is though. For me personally, 30Hz to 20kHz would be exciting to have access to.

        • Tomasz

          You can get this for $60. It’s good enough for bass and most speakers/headphones have a nice flat response for mid- to high-frequencies. You can get the free REW software that will do sine sweeps for you. It will even generate EQ settings that work with EqualizerAPO.
          That’s what I did and it improved my audio by (subjectively) 20%.

          Furthermore, you need to take into account that people have different frequency responses, esp. in the high frequencies the differences can be dramatic. The ISO curve is a kind of average.

  • Tiffany

    Thanks so much. I used this tool to find my starting note singing the national anthem at a conference this year.

  • Giovanni Ciriani

    Tomasz, I think it is important to let users testing their hearing or their tinnitus frequency, to use headphones. Without headphones, one may think that there is a volume drop, or a hearing drop, when in fact the ears are actually in a zone of subtraction between two loudspeakers of the PC.

  • Rob Ward

    The online tone generator is great … I use it to check the accuracy of my electronic tuners, find the frequency where my speaker cabinets rattle, to tune homemade windchimes. Its useful, thanks.

  • Nathan


  • Nathan


  • fred

    Thank you. Great tool

  • Jack

    Tomasz, The application is a great tool but there is one thing that would make it more useful, i.e., a way to select a range of audio frequencies to sweep and the rate the frequency changes. My use of your application is to data log a range of frequencies to graph the transfer function of audio filters and frequency response of other audio hardware. It is really difficult to step the frequency 1Hz at a time in sync with the sample rate of the data logger. Not being a programmer I have no idea of how difficult adding this feature would be but would be like to hear your thoughts on the issue.

  • Don Puryear

    Thank you, Thomasz! I enjoyed your article.

    When I was in college, I was treated for tinnitus. The condition never went away, and I still have it to this day. During multiple hearing tests over the years, the pitch I produced vocally and the pitch I identified aurally as matching the tinnitus has been 440 hz. Decades after my college experience, I was bothered enough by the tinnitus — or more specifically, my awareness of it — that I saw an otolaryngologist who tried a number of treatments. He was unable to cure or lesson the tinnitus. In testing, he confirmed that my tinnitus was consistently 440hz.

    I’m 50 now, and I still have the tinnitus. I’m able to “tune out” it out whenever there are other ambient noises, but otherwise it’s crystal clear & distinct. For the last 30 years, I’ve slept with white noise in the background to drown out the tinnitus.

    Your article was great, and the online tone generator was fun! I enjoyed checking the pitch of my tinnitus — Even today, it’s still 440hz! 🙂

    • Dana

      Hi Don, I have tinnitus, too… I was just browsing by and wanted to add a tidbit about your tone: it is special because A 440 is the tone that bands and orchestras use as a reference for tuning their instruments. It is known as the “international standard pitch.” You are a walking tuner!

  • Jb

    Excellenr! Just friggin brilliant! Love this thing!

  • Norman Paterson

    This is close to what I want for an experiment – with a slight modification it would be ideal. I want to demonstrate the difference between a scale where the frequency increases arithmetically (e.g. every interval increases frequency by 50 Hz) and geometrically (e.g. every interval increases frequency by 10%). Your tool does this but only in fixed steps of 1 Hz or 100%. Any chance you could make these adjustable quantities? I’d love you forever! PS The demo is in 4 days!

  • Ingrid Lindberg

    I agree with many others. Its an excellent tool. I use it to test noise frequency at low levels 35hz. Thank you!!!

  • Reginald

    I was looking for something like this. I am learning to write music for a particular part and needed to know if I have the right note in the correct octave. because of the range of the instrument, knowing the frequency and octave number becomes important when applying the correct notes on the music staff.

  • Hussain Chagla

    I by chance found this audio generator on web. It is useful test instrument
    for those who can use it..It can be used for measuring power output & response of Power amplifiers. Also check response ,power handling
    capacity of loudspeakers.
    Its nice & handy, I dont have to carry separate audio generator. Any more.
    One suggestion, please add Pink Noise Generator to it.
    Hussain. Karachi-Pakistan.

  • Russ Lynch

    Just what I needed to quickly check my hearing thru headphones.
    Beats those other hearing tests by a mile. Keep up the good

  • Soundman

    Can you please make it so you can adjust by .1, .2, .3 etc. ? Example 111.1, 212.1 313.1, etc. for amazing reasons I shall explain once done. Thank you!

  • Walter B

    Thank you. I determined the frequency of my tinnitus with this.

  • stevieblueboat

    The note palate you have added is fantastic! Thanks for the work you’re doing.

  • Richard

    A very useful test tool. Most appreciated.

  • Ferroll

    This was perfect for checking my DIY 18″ Subwoofer Enclosure. I tuned my enclosure to 38 Hz, and all the frequencies below 40 are the loudest. Thanks for this easy to use application.

  • Will

    This is great although I think my headphones are limiting the frequency a bit.

  • Jarrod Haning

    YES! This right here!

    I have been searching for this for years, even tried having some computer graduate students tackle it as a class project – but they were not able to solve these problems.

    This could be very helpful for music students learning intonation if it was in a mobile app form with 4 sliders which allowed you to build 7 chords (4 note chords) and check your answers as compared to relative or just tuning.

    May I access the code? Or, may I hire you to compile it into an app that could be shared with music teachers?

  • Easan

    Thatnk you for this wonderful tool. I wonder if there is a keyboard instrument that plays notes in the 12k hz to 20k hz range. I would like to compose and play music in that range.

  • Danny

    This is a great tool. I would like to be able to modulate back & forth between two designated frequencies in a pulsing rhythm. For experiments.

  • Dana

    Thank you for your useful site. Since 9/10/2016 I’ve been suffering from tinnitus, a single pure tone stuttering like a telegraph in one ear. Your straightforward tone generator has helped me track the pitch. I noticed the tone started around 180 Hz (around F#3) and has been slowly but surely gone down in pitch, currently 155 Hz (almost to D#3). So it crept 3 half-steps down over the last month. I am wondering why (physiologically or mentally) the pitch would be going down – whether this is a good or bad sign, or does it mean anything at all. Any information or theories would be appreciated.

    • TTTS sufferer

      Dana, it could be you are siffering from Tonic Tensor Tympani Syndrome, and that the pitch lowers as your Tensor Tympani becomes less tense. For me, the pitch certainly rises as the tension and volume rises. You should look into it

  • TTTS sufferer

    Hello, and thank you for the great work. I suffer from TTTS, with a pure tone tinnitus accompanying it when I have my bad days. Finding the tone (it fluctuates) and blasting my ears with it seems to give me some relief.

    It would be great if you developed this as an app for Android and Ios, so that one could use it while on the go without having to be online. Preferrably multitrack, with volume sliders for each track. It’s also important that both frequency and volume sliders are large in size, to accomodate fine tuning. There are tone generator apps in the market, but I so far haven’t found any that lets you adjust the frequency while the sound is playing, and your generator’s ability to do so makes it hugely useful.

    I would pay for and recommend such an app

  • Hairma Cutma

    It is a good tool to check out a dog’s hearing, also for dog repellant, lol!!!!!

  • Marc Dingena

    Hi. I have pure-tone tinnitus for as long as I can remember. So long, in fact, I can happily say it doesn’t bother me so much.

    Do you have any idea how hard it is to explain tinnitus to people who don’t have it? I usually can’t do any better than “that sound you hear in bed after you’ve been to a loud concert”.

    This tool has given me a way to let others (my wife for example) experience what I hear 24/7. 9946 Hz…

    Thanks for making this.

  • Tomas

    Great tool to practise unfretted string instruments like fretless bass 😉 Love it!

  • alicia

    wow this is amazing! I have had tinnitus for a long time i think but it has recently started bothering me. Every time i listen to you tones even though i haven’t figured out my exact frequency yet, my tinnitus disappears for a while. It’s nice to be able to experience silence for a bit. Thank you so much!

  • Lendon

    LOVE THIS TONE GENERATOR!!! Can experiment mathematically with different frequencies!!! Thanks so much for making it. I open two or more tabs usually to test out harmonization. Again I really like this tool! Thanks!

  • raymond schep

    Ha ha now don’t need to buy a rpm meter to set the idling of my car, 1000 rpm is 17 hz, I can do it by ear, however why do they claim the lower range of hearing is 20 hz I can easily hear down to 5 hz….but no chance at age 70 of hearing 20,000 hz, best I can do is 8000 hz.

  • Anonymous_user01

    Could you add a option to download the tone?

  • Rachel

    Hi there
    Can you tell me how I might record or download the tone I have identified as useful?
    It would be for personal use at this stage

    • Tomasz P. Szynalski

      Rachel, you cannot download an audio file at this point. This kind of functionality is not supported by Web browsers very well. You can use the Get Link button to make a direct shortcut to your chosen tone.
      If you need a sound file with a specific frequency, I could generate one for you.

  • Asghar Kazmi

    Have you thought of giving users the option to change the phase of the signal so that they could possibly reduce or cancel the sound from another device. I have tinnitus and would like to see if it is possible to use this method to reduce the level of the sound in my head.

    I am seeking a tone, 180 deg out of phase, to 8460 Hz. This is the frequency of the high pitch sound that I have identified to be ringing in my head 24/7. Your tone generator helped me to identify the thing. Thanks.

    • Tomasz P. Szynalski

      I don’t think that would work — tinnitus doesn’t have phase because it’s not an actual sound wave. It occurs on the level of neurology. When you hear e.g. 5 kHz, some neurons in the auditory cortex start firing. They don’t fire at 5 kHz. The frequency is encoded by position, i.e. 5kHz and 4kHz correspond to different neurons, not the same neurons firing at different frequencies! (In other words, the brain does an inverse Fourier transform to decompose the sound into frequencies — this destroys the phase information.)
      Otherwise, you would hear a difference every time you started the tone generator (every time you started it, it would be at different phase with respect to your tinnitus).

  • Dissonance

    This is a great tool! It’s the only online tool I found that can do 1/1000 of a Hz. It would be great if you could play two different tones at the same time so you can hear intervals and beats.

  • Mar

    Thank you very much! It helped me a lot 🙂

  • Clemm

    It is a great thing you have done here !
    Thank you so much for the sharing 🙂

    (I am using it to hear and heal with the 432 Hz instead of 440 Hz).
    (28,5 / 75,75 / 91 / 128 / 192 / 288 / 432)
    witch is frequencies of Tibetan Healing Sounds.

    But thanks to you, it is possible to access very low frequency for the body that is not possible with Tibetan bowl.

    Thank you my friend 🙂

    • Clemm

      I forgot to mention that to make 0,5 or 0,75, I use the arrows with the mouse and then with the keyboard. By pressing the arrow “right” of the keyboard for example, the number won’t change before I press it 4/5 times so I know where I am exactly between 0,25 0,5 0,75 …

      For the ones who make an interest with this, here are the frequencies you can use for each chakra to heal :
      1 : 14,25 / 28,5 / 57 / 114 / 228 / 456 / 912
      2 : 37,875 / 75,75 / 151,5 / 303 / 606 / 1212
      3 : 45,5 / 91 / 182 / 364 / 728 / 1456
      4 : 64 / 128 / 256 / 512 / 1024 / 2048
      5 : 96 / 192 / 384 / 768 / 1536
      6 : 144 / 288 / 576 / 1152 / 2304
      7 : 216 / 432 / 864 / 1728 / 3456

      I just discovered your tool yesterday and what I can say is : “it gives a lot of energy using is as I do”. Just try to play :
      * (28,5 +128+432) at the same time (1+4+7)
      * or (75,75+192) (2+5)
      * or (91+288) (3+6)
      and see what happens for fun ! 😉

  • Meletiy

    I used the tone generator for an IB Physics HL investigation on Chladni figures.
    It was very useful. Thank you so much!

  • Robert Blackham

    New use: testing the effectiveness of noise-cancelling headphones, at different frequencies.

  • Jim

    Would it possible to request an auto slider?

    Say x Hz to y Hz over z Seconds?

  • David

    The tone I get on by iPad Air IOS 10.3.1 is not clean. There is a cackground noise, like static, that is most noticeable (higher amplitude compared to selected frequency) at the low end than at higher frequencies. It’s like a modulated rhythmic crackling, that makes the generator all but useless.

    • Tomasz P. Szynalski

      What is the period of the crackling? I tested tones around 100 Hz on my iPad Air 2 (with Safari) and I could’t hear anything — other than the normal distortion of my headphones (which is present regardless of the device or generator used).

  • Moses

    I just found your tool and it’s fantastic. Thanks!

    How easy or difficult would it be to add a selector for a square or sawtooth wave instead of a sine wave? Sometimes I have trouble matching octaves with a pure sine wave.

  • Andari

    heh. at 37hz my window in my room doors is vibrating like crazy it vibrating soo hard it makes noise lol

  • Ian Bett

    Hi Tomasz.

    What a great little program you have put together.

    I will use it to improve my studio monitor design and acoustic
    treatments for the room.

    Well done!

    Ian Bett – Western Australia

  • cs127

    Only sine waves?

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