Frequently Asked Questions
Everything we've been asked about Gesture Synth — from how hand tracking works to why your video never leaves your computer. If your question isn't here, see the Contact page.
Basics
What is Gesture Synth?
Gesture Synth is a free, browser-based musical instrument that uses your webcam to track hand gestures and turns them into live music — chord pads, theremin tones, and more. It runs entirely on your device, with no install and no account.
Do I need to install anything?
No. Open the Play page in Chrome or Edge, allow webcam access, and click "Enable audio". That's it. No download, no plugin, no signup.
Is Gesture Synth really free?
Yes. Gesture Synth is free forever. No subscription, no in-app purchases, no upsells. Just open and play.
Tracking & privacy
How does Gesture Synth track my hands?
Gesture Synth uses MediaPipe Hand Landmarker — a Google open-source machine learning model that runs as WebAssembly inside your browser. Video frames are processed locally and never leave your computer.
Does Gesture Synth upload my camera video?
No. Hand tracking in Gesture Synth is fully on-device. Frames are processed locally and discarded immediately. No video upload, no telemetry, no cloud.
What does Gesture Synth send to the internet?
Only anonymized usage data through Google Analytics 4 (page views, country, device category). When you click "Enable audio" or open settings, no personal data is sent. See the Privacy page for details.
Music theory
What chords can I play?
In Gesture mode, your left hand picks from I · vi · IV · V · ii (plus borrowed VI and VII). In Theremin mode, you can play any pitch from roughly 65 Hz to 1200 Hz. See the Chords page for what each chord sounds like.
Do I need to know music theory?
No. The chord labels (I, IV, V) are written next to each gesture so you can experiment. If you do know theory, you'll find the mapping is fast and intuitive.
Can I change the key?
Yes. Use the key selector in the top bar to pick any starting note. The default is A (220 Hz).
Browser & device
Which browsers are supported?
Chrome and Edge on desktop. Other Chromium-based browsers should also work but are not officially tested. Safari support is partial (Web Audio works, MediaPipe may not load in all versions).
Does Gesture Synth work on mobile?
Currently Gesture Synth is optimized for desktop browsers. Mobile support is on the roadmap. The webcam + MediaPipe stack works on mobile but the UI was designed for a larger screen.
Why does my camera block the page?
Browsers show a permission prompt the first time any site asks for the camera. Click "Allow". If you previously clicked "Block", go to your browser's site settings and reset the permission for gesturesynth.art.
Recording & sharing
Can I record what I play?
Yes. Click the Record button in the top bar. After a 3-second countdown, Gesture Synth records both your webcam and the audio output as a single WebM file. Click Stop and you can download or share it.
What format is the recording?
WebM with VP9 video and Opus audio. Most modern players can open it. If you need MP4, you can convert with any free transcoder.
Where do recordings go?
They stay on your device until you download or share them. Nothing is uploaded.
Still have questions?
Contact us →