Oura

Oura Ring 4

The most refined sleep and recovery tracker, and the one with the most published validation behind it — if you can live with a subscription.

Year one: $421; inc. subscription
Hardware: $349; From $349 (Heritage) / $499 (Ceramic)
Subscription: $5.99/mo; required
Battery: Up to 8 days

Oura is the default smart ring for a reason: the sleep staging is the best-validated of any consumer wearable, the temperature sensor is genuinely useful for illness and cycle tracking, and the hardware disappears on your finger. The catch is the model — you buy the ring and then rent the insights. If you stop paying, you keep almost nothing. It is also, like every wrist- or finger-worn device, an estimate: it infers sleep stages from movement, heart rate and HRV rather than measuring brain activity.

Is the measurement validated?

The strongest evidence base in consumer sleep tracking — independent polysomnography comparisons show good agreement for total sleep time and reasonable stage agreement, well ahead of most wrist wearables. Still an estimate, not a sleep study.

What it measures · 13

Sleep duration
REM sleep
Deep sleep
Core / light sleep
Awake in bed
Heart-rate variability (HRV/SDNN)
Resting heart rate
Heart rate
Respiratory rate
Wrist / skin temperature (sleeping)
Blood oxygen (SpO₂)
Steps
Active energy burned

Does it reach your record?

✓ Syncs

Writes to Apple Health, so the iOS companion picks it up automatically.

Explore your health record →

Best for

Anyone whose main question is 'how well did I sleep, and am I recovered?'

Watch out

Subscription is mandatory and rings are hard to resell. Size carefully — fingers change size with temperature and weight.

Manufacturer site

Price checked 2026-08-09 and quoted at MSRP — hardware pricing moves. Consumer devices estimate rather than diagnose; discuss anything clinical with your doctor.

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