Google trained phones to measure heart rate using the front camera.

Google has created a way to measure pulse using the front camera of a smartphone

The company announced a new technology called *passive heart rate monitoring* (PHRM). With it, you can determine your heart rate simply by looking into the selfie camera. This opens up the possibility of replacing traditional fitness watches and bracelets with the same device that most people already have.

How PHRM works
1. Launch – the user unlocks the phone using facial recognition.

2. Capture – a short video (8 seconds) starts recording at the same time.

3. Analysis – a machine‑learning algorithm processes changes in skin color on the face caused by blood flow and calculates the pulse.

These fluctuations are too small to be seen with the naked eye, but modern smartphones can capture them thanks to high frame rates and precise cameras.

Why it matters
- Wearable devices (fitness bracelets, smart watches) are purchased less often than smartphones.

- If pulse can be read directly from the phone, users won’t need to wear a separate gadget.

- The technology has already shown high accuracy: the difference with Fitbit Charge 6 data is only 5 beats per minute.

How the system was tested
Metric Data Number of videos More than 350,000 participants 700 volunteers Skin color included people with various shades, including dark skin Real‑world conditions Participants wore ECG and Fitbit for a week

Despite good results, PHRM is not yet perfect:

- Dark skin sometimes reduces accuracy.

- Head movements, talking, and other everyday activities can cause errors.

- Privacy – Google addresses the issue by processing data locally on the device and using facial authentication.

What’s next?
PHRM remains a research project, but the prospects are clear: smartphones will be able to monitor heart rate without additional devices. This will make cardiac health monitoring more accessible to a wide audience.