Google explains how it built and tested Pixel 8 Pro's thermometer for body temperature

The recently arrived Pixel January Feature Drop unlocked the full potential of the Pixel 8 Pro’s thermometer, enabling body temperature readings. The Google team seems very proud of this, and in a post they have revealed some of the work that went into developing the feature, as well as details about how it works.

One of Google’s boldest claims regarding the body temperature readings offered by the Pixel 8 Pro’s thermometer is that the results are ‘medical grade’, and the company appears to reaffirm this in the post. More specifically, they say their tests yielded an error margin of just ±0.3°C compared to a temporal artery thermometer.

The idea was born from Ravi Narasimhan, technical research and development leader at Google, who was working on a project to develop a miniaturized device capable of reading body temperature using infrared sensors. Over time, that project evolved and led to the integrated thermometer in the Pixel 8 Pro, with the idea of avoiding having to carry additional devices if you need to measure your body temperature.

The post confirms that Google only obtained the necessary certification from the FDA in December 2023, which is why the feature was not available before. That said, the company only obtained certification for the United States, so, at least officially, only the Pixel 8 Pro from the United States will receive the ability to read body temperature. The company does not offer details about whether they are working on obtaining certifications for more countries.

The operation of the feature is based on the detection of infrared radiation emitted by all bodies (heat) using the integrated sensor in the rear camera module. Using it is as easy as opening the Thermometer app, bringing the camera module closer to a person’s forehead and sweeping across. According to Google, this last step and the wide FOV (more than 130°) of the Pixel 8 Pro’s infrared sensor allow it to scan the temporal artery, making it more precise than forehead thermometers that only stay in the center.

After obtaining the readings, an algorithm processes them and calculates the person’s body temperature. If you want to get the most accurate readings possible, Ravi recommends bringing the sensor as close as you can to the person’s forehead, but without touching it directly to avoid situations such as the potential spread of germs. In fact, with this in mind, they also developed a system based on the Pixel 8 Pro’s LDAF sensor that detects whether the device is close enough to the forehead to offer an accurate reading, including haptic and audible instructions to guide you through the process.

Basically, the body temperature readings from the thermometer integrated into the Pixel 8 Pro are the result of a lot of research, testing, and obtaining certificates. Surely, in the coming days, comparative tests will begin to emerge to verify that they are as accurate as Google claims.