Four wearables dominate the longevity tracking market — and they're each optimized for different things. Here's how Whoop, Oura, Garmin, and Apple Watch compare on the metrics that actually predict healthspan.
By 2026, four wearables dominate the longevity-conscious consumer market: Whoop 5.0, Oura Ring 4, Garmin Fenix 8 (and the lighter Forerunner/Venu line), and Apple Watch Ultra 3. They overlap substantially but optimize for different things. This guide compares them on the metrics that actually predict healthspan and helps you pick the right one for your goals.
Most consumer wearables measure four core signals well: heart rate (continuous), heart rate variability (HRV), sleep stages (estimated from movement and HR patterns), and skin temperature trends. From these, they derive the metrics that actually predict longevity outcomes:
Less reliably measured: stress (skin conductance proxies are limited), blood oxygen during exercise, calorie burn (consistently overestimated by 20–40%).
A subscription-only wrist or upper-arm strap with continuous HR, HRV, skin temp, and respiratory rate. No display. Battery 4–5 days; charges via wireless slide-on pack you swap without removing the strap.
Strengths: best-in-class HRV measurement; sleep stage classification; strain-recovery framework with the most prescriptive feedback; excellent app for trend analysis; popular with athletes who want training load guidance.