Piano Keyboard Frequency Chart
Every key’s pitch in Hz · tap a key to hear it · A4 = 440 Hz, equal temperament
How to play
- Tap any key to hear it and read its exact frequency in Hertz (cycles per second). The big panel shows full precision; each white key shows a rounded value.
- Pick a note above the keyboard to light up every key with that name across the octaves.
- White keys are the natural notes C D E F G A B; the black keys are the sharps/flats between them — grouped in 2s and 3s.
- Go up one octave and the frequency doubles (A4 = 440, A5 = 880). Each semitone multiplies the pitch by 21/12 ≈ 1.0595. Tap two notes in a row to see their frequency ratio — simple ratios like 3:2 (a fifth) and 2:1 (an octave) sound the most consonant. A440 tone plays the reference. Vol sets volume.
- Keyboard — Tab to a key or control, Enter/Space to activate. Scroll the keys sideways on small screens.
The following is an interactive piano keyboard that displays frequency in Hertz for every note played. Simply click on key to listen to sound it makes and view its accurate measurement. It also allows you to measure and compare intervals. It also shows how equal temperament divide the octave into equal mathematical steps.
A standard piano is covered by a keyboard that includes all octaves from A0 to C8. All white keys are represented as natural notes from C to B while all black keys indicates both flats and sharps. Note names and their respective octave is printed on each key. Simply touch any key with your mouse/trackpad and note will sound. The layout of the keyboard make sense as the black keys are grouped together into common patterns of three and two keys.
How to Use the Interactive Piano Keyboard
Above the keyboard, there’s also a row of buttons which highlight individual note names. You click on one and it will light up anywhere else that note appears in any octave. So, if you press the ‘C’ button, then you can see where C’s are located throughout the instrument’s range. This is useful if you’re curious about how often a note name repeat at a certain frequency.
Below the controls is a very informative display panel that provides precise details of selected note. It indicates the note’s name and its actual frequency in Hertz. It also shows its relationship to standard pitch (A440). You can also see formula by which frequency was derived from this starting pitch. When you choose a different key this section will refresh immediately providing instant feedback on chosen pitch.
If you want to compare two notes just tap one key then tap another. The widget will find the interval between those two note as well as their frequency ratio. This ratio exposes the mathematical basis of intervals such as major thirds or perfect fifths. It explains why simple integer ratios result in consonant sounds while more complex ones results in dissonance. In this way it makes keyboard a study aid for harmony.
The A440 tone button is the reference pitch that instruments uses for tuning around the world. The note is A at 440 Hertz which sits at the centre of the equal temperament system. Simply press this button first to establish your base frequency then experiment with others. You will be familiarising yourself with level of pitch most musicians work in.
There’s also a volume slider in the control bar where you can make tones as loud as you’d like. Just drag the slider until you find a comfortablely listening level for the room. Whether you’re using speakers or headphones, this control ensures that you’ll hear them clearly. By adjusting the volume you can concentrate on pitch difference without any potential for distortion.
The widget expands to take up your whole screen when you click it, giving you a bigger view of keyboard. The buttons is easier to tap and the text is easier to read in this mode. It’s good if you want to use the tool on a big display or just need to look closer. At any point you can exit full screen and return to compact view.
The other useful feature is the toggle button that offers tips and explanations about how to use it. It outlines the keyboard, offers guidance on how to use the interval comparison, and even includes an explanation of what all the symbols mean in interface (interval names and math formulas). If you’re not sure how something works or want a refresher, this is where to go.
With this widget, you can play around with pitch and discover its change through the range of frequencies. Play basic melodies and listen to how frequencies pile up in time. Then experiment with interval relationships and experience difference between the ones that are stable and those that cause tension. Together the audio output and the visual feedback provides an obvious example of acoustics of music.
Explore the keyboard and check out frequency values. This tool is meant for learning, so there is no wrong way to use it. Just click around, experiment with volume and get your ears around what pitch is. Then just start playing to discover how the mathematics of music becomes sound.