Sleep Accuracy Study
Best: Apple Watch Ultra 3
89% stage agreement. Best REM. Apnea detection works.
Dedicated: Oura Ring 4
87% agreement. Superior HRV from finger.
Budget: Xiaomi Band 9 Pro ($59)
78% agreement.
Rankings
- Apple Ultra 3: 89%
- Oura 4: 87%
- Samsung Watch 7: 84%
- Garmin Venu 4: 82%
- Whoop 5.0: 81%
- Fitbit Sense 3: 80%
- Xiaomi Band 9: 78%
