Loop

Polar Loop is an armband from 2025, sitting in the mid-range band at an indicative $200.

It reads 13 of the 33 signals this comparison tracks. Nothing at all from body composition. Rarer readings it does take: sleep efficiency.

By sensor class: 5 at high accuracy and 4 at consumer grade. That grade is my classification of the hardware, not a lab test. Those readings come from an optical heart rate sensor and an accelerometer.

Its 8 days per charge are the 7th longest of the 11 devices of its kind here that publish a figure. Rated WR30 / 30m, fine for swimming. It weighs 29 g. Dimensions 42 x 27 x 9 mm. No subscription is required.

Screen-free band worn around the clock, September 2025. No SpO2, no skin temperature, no fitness test. Distance needs the phone, so it does not count as measured by the device.