Keys play notes from the computer keyboard; left and right arrows change octave, up and down change loudness, hold Space for the sustain pedal, Escape stops every sound.
The letters on the keys show which computer key plays them. With the A row layout, A to ' are the white keys and W E T Y U O P the black ones. The two-row layout puts one octave on the Z row and the next on the Q row, with the black keys on the rows above them, the way music trackers and most music software do. The arrow keys move the octave and change how hard the keys are struck. Hold Space for the sustain pedal.
Yes, in Chrome, Edge, Opera and Firefox (Firefox asks you to allow a small site permission add-on first). Plug it in, press Connect MIDI keyboard and allow access. Velocity and the sustain pedal (CC 64) work. Safari doesn't support Web MIDI, so on an iPhone, iPad or Mac in Safari use the screen or the computer keys.
The grand piano is the Salamander Grand Piano, a Yamaha C5 recorded by Alexander Holm and shared under Creative Commons Attribution 3.0. Every third note was recorded; the notes in between are the nearest recording, retuned. Playing softer makes the sound darker as well as quieter. The two other sounds are synthesized in your browser and need no download.
Recording keeps the notes you play, how hard, and the pedal, not the audio, so a take is a few kilobytes. Takes are saved in this browser's local storage on this device. Download a take as a MIDI file to open in GarageBand, Logic, MuseScore or any music software, or as a WAV file, which is rendered on your device with the sound you've chosen. With the metronome on, the MIDI file's bars line up with the clicks. Export all saves every take as one file you can import again later, here or in another browser.
Want a tuner, chords and scales, or a drum machine? They're on music.gripe.