Your left hand chooses
Your palm or the back of your hand may face the camera. Use the fixed index-first combinations for I–V, index + pinky for VI, add your thumb for VII, or make a fist for silence. Wrist tilt selects Major or Minor.
A browser instrument powered by movement
Play music
with your hands.
Use your left hand to choose what you play. Use your right hand to shape how it sounds. Then sing, record and share the result.
No instrument or music theory required. Camera access starts only when you enable it.
LIVE INSTRUMENTREADY
LEFT HANDAm3 fingers · active
RIGHT HAND78%volume · bright
Your voice is optional Record the performance
Two hands. Two simple jobs.
You do not need to understand music theory before you play.
Your right hand starts and shapes it
The chord stays silent until your right hand appears. Move higher for louder and lower for quieter, tilt to change the filter, and show 1–4 fingers to change the voicing.
Try 1 → 4 → 5 → 1
Keep one right-hand finger raised. Change your left hand slowly through 1, 4, 5 and back to 1, then hum or sing anything over it.
Think of the numbers as buttons, not music theory.
“1” is a comfortable starting sound. “4” opens the music up. “5” adds a little tension. Returning to “1” feels like coming home.
See the beginner guideFour ways to play
Start with the sound you want.
Gesture Chords
Choose harmony with your left hand. Shape volume and tone with your right.
Open modeOnline Theremin
Move through the air to control continuous pitch and volume.
Open modeMelody
Turn movement into individual notes for simple melodic experiments.
Open modeKeyboard Mode
Keep playing when a camera is unavailable or you prefer keys.
Open modeWant a starting point?
Follow a song. Keep your freedom.
Guided Songs show lyrics, sections and optional chord references. Your hands still make the music.
Browse Guided SongsRecord your performance
Record the instrument, optional voice and camera performance locally in your browser. Download or share when your take is ready.
Learn about recordingCamera privacy
Camera and microphone access begin only after you choose to enable them. Leaving the instrument stops the active media streams.
Read privacy and camera useFAQ
Questions before you play
Do I need music theory?
No. Treat the hand gestures as simple sound buttons and learn by listening.
Does the site play without a camera?
Yes. Keyboard Mode is available when the camera is unavailable or you prefer keys.
Does the app automatically play the song?
No. Guided Songs show optional references; your hands still control the sound.