Your Wi-Fi Router Can Detect Your Breathing Through Walls, and the Science Is Real

A viral post from an engineer claiming that“breathing is enough to give you away”has been seen by nearly two million readers, and the research backs it up. Wi-Fi waves reflect off your chest and change with every breath, letting a router detect breathing patterns up to five meters away at 95% accuracy, and heartbeats up to one meter at 83%. The same signals can identify presence, posture, movement through walls, and how many people are in a room.

This isn’t fringe science. A 2022 NIST report framed Wi-Fi breathing detection as a health-monitoring tool during the COVID-19 pandemic, and the CIA has reportedly used similar sensing technology to locate a stranded pilot in Iran. The upside for medicine is obvious. The privacy questions are less comfortable, especially since most people assume their router is a passive device that just delivers movies and music.

The bigger issue is that privacy law hasn’t caught up with sensing tech. Your router can gather intimate health details without consent, and there’s little guidance on what companies or governments can do with that information. Do you think homeowners should be able to opt out of Wi-Fi sensing, or is early health detection worth the tradeoff?