Sleep Tracking Ring

The sleep tracking ring I started wearing in February has changed how I think about my nights, mostly because I forget it's on my finger. The absence of friction is what makes the data reliable. Titanium and about 4 grams, the ring is light enough that I don't feel it under a pillow or when I turn over. Sensors on the inside measure heart rate, skin temperature, and blood oxygen without needing a charge for 5 days. The dashboard shows sleep stages in a stacked bar chart: deep sleep in dark blue, REM in purple, light sleep in pale gray. Scrolling through 2 months of data, I can see patterns I never would have noticed from subjective memory alone. My deep sleep drops to almost nothing on nights when I study past midnight, even if I get the same total hours. Correlation has been consistent enough that I've started treating 11 PM as a hard stop for screen time. Temperature tracking picks up changes before I feel sick. Twice this semester the app flagged a 0.5-degree elevation the night before I woke up with a sore throat, giving me time to load up on fluids and rest before it got worse. A finger has capillaries close to the surface that give more accurate readings than the underside of a wrist, where tendons and bones interfere. That's partly why this works better than a wrist tracker. The morning readiness score synthesizes all metrics into a single number from 0 to 100. Reducing a night of sleep to a number makes me skeptical, but days when it reads below 60 do correlate with how groggy I feel. No push notifications, no product suggestions, which is rare for a health tech company. Restraint in the software matches restraint in the hardware. My roommate asked if wearing a ring to bed feels weird. After the first 3 nights I stopped noticing it entirely. The data has made me more protective of my sleep in a way that vague advice about "getting 8 hours" never could, because now I can see exactly what happens when I don't.