The depth of waterproof fitness trackers depends on the model of the tracker, though it ranges between 20 meters and 100 meters. The average depth is 50 meters.
The Basis Peak is a top-rated fitness tracker that is waterproof in depths up to 50 meters. This device tracks the heart rate and physiological data while swimming. The Polar Loop tracker has one of the lowest depths at 20 meters. It is an inexpensive fitness tracker that works well in swimming pools and shallow waters. The Runtastic Orbit fitness tracker has one of the biggest depths for being waterproof at 100 meters. The LifeTrak Move C300 works at up to 30 meters.