Virtual Piano - Play Piano Online with Your Keyboard

This is a real playable instrument, not a picture of one. The keyboard spans three octaves — C3 to B5 by default, shiftable from C1 up to B7 with the octave buttons — and every key produces a genuinely synthesized tone: two oscillators (a triangle wave for the body of the sound and a quieter sine an octave above for roundness) shaped by a fast attack and a natural decay envelope. Turn on Sustain and notes ring close to three seconds, like holding a piano's damper pedal. There are three ways to play. Click or tap the keys directly — they are drawn with plain CSS, so they work identically on desktop and touch screens. Or use your computer keyboard the way virtually every music app maps it: the home row A S D F G H J K L plays the white keys starting from the lowest C on screen, and the row above — W E T Y U, then O and P — plays the black keys sitting between them. That mapping mirrors the physical geometry of a piano, which is why it has become a standard: A-W-S-E-D is literally C, C-sharp, D, D-sharp, E. Finally, if your browser supports Web MIDI (Chrome and Edge do), press Enable MIDI input and play a connected MIDI keyboard directly. The frequency readout under the keys is a small music-theory lesson in itself. Modern instruments use twelve-tone equal temperament tuned to A4 = 440 Hz: each semitone multiplies frequency by the twelfth root of 2, about 1.05946. Play A4 and you will see exactly 440.00 Hz; play C4 — middle C — and you get 261.63 Hz; go up an octave to C5 and the number doubles to 523.25 Hz. Watching the numbers while you play makes the logarithmic nature of pitch concrete in a way a textbook diagram never quite does. Two octaves is also enough real estate to learn the shapes that matter. Find the white-key major scale starting on C. Build intervals: a perfect fifth is seven semitones (C4 to G4), a major third is four (C4 to E4). Stack them into a C major triad, then slide the third down one key for C minor. Because the note names can be shown on every key, you can connect what you hear, what you see, and what the notation calls it — then hide the names once the geometry sticks. Everything runs locally in the page: nothing is recorded, nothing is uploaded, and after the first load no network connection is needed at all.