Wi-Fi does more than connect your phone to the internet. Its radio waves travel through a room and bounce off walls, furniture, and people. When you move—or even breathe—you make tiny changes in these waves. Special software can study these changes and learn information about you. (nist.gov)

Researchers call this technology “Wi-Fi sensing.” It can detect whether someone is in a room, count people, recognize gestures, and watch breathing. Some systems can also tell people apart by studying how their bodies affect Wi-Fi signals. Others look at each person’s walking style, which is often called gait. (arxiv.org)

In August 2026, researchers introduced a system named Argus. It did not require people to carry phones or wearable devices. In a test involving 154 people, it correctly identified a person about 79% of the time after studying six seconds of Wi-Fi data. After studying 60 seconds, its accuracy rose to about 85%. However, the researchers also reported problems when the system moved to a different room or met an unknown person. (arxiv.org)

This means that Wi-Fi cannot simply discover your name. First, a system usually needs examples of your signal pattern. It then compares new data with the patterns it has already learned. Room conditions, other people, and changes in movement may influence the result.

The technology could be valuable. A smart home might notice that an older person has fallen, check unusual breathing, or turn on lights when someone enters. In 2025, IEEE published a new technical standard, IEEE 802.11bf, to support Wi-Fi sensing. (standards.ieee.org)

Still, there is an important privacy question. Unlike a camera, Wi-Fi sensing does not create a clear picture of your face. Yet it may observe you without requiring a device in your hand. As the technology improves, clear permission, strong security, and simple controls will become increasingly important.