Oura Ring 4

Weighing as little as 3.3 grams with a 2.88mm thin titanium band and recessed interior sensors, Oura Ring 4 dynamically selects among 18 optical signal pathways to maintain continuous sleep-stage, HRV, daytime stress, and temperature accuracy even as the ring rotates. Engineered by ŌURA Health Oy (All-Titanium Smart Health Ring (Sizes 4–15)) at a reference MSRP of $349 + $5.99/mo, Oura Ring 4 pairs Screenless (Companion iOS & Android App) with 18-Path Smart Sensing PPG, SpO2, Skin Temp, HRV and Up to 8 Days. It is purpose-built for sleep-focused professionals and mechanical watch collectors who dislike wrist screens at night, with key strengths including flush titanium interior eliminates the raised sensor bumps of gen 3; industry-benchmark readiness, sleep, cycle, and symptom radar analytics.