Camera + flash PPG. Estimate only — not a medical device.
Place your index fingertip flat over the rear camera. Gentle pressure — don't press hard.
Turn on the flashlight — we do it automatically on Android/Chrome. On iPhone, hold the phone in a well-lit room (Safari can't toggle the flash).
Rest your hand on a table. Breathe normally. Any movement adds noise to the reading.
We watch tiny red-channel changes and estimate BPM. Stay still until the ring completes.
Measurements you take will be saved here on this device. Sign in to sync them across devices.
PPG estimates are typically within ±3–5 BPM. Not for medical use. Some browsers (especially iOS Safari) can't control the camera flash — measurements still work under bright ambient light.