Review · Health & fitness
Circular Ring 2 review
A four-gram titanium ring with four-stage sleep, a silent vibration alarm, single-lead ECG and blood-pressure trends, sold with no mandatory subscription.
By the HearSmart research desk · Updated November 9, 2026
- Performance (40%)
- 8.4
- Ease of use (25%)
- 7.9
- Value (35%)
- 8.1
Circular Ring 2 is the pick here for people who want the ring itself to wake them. Its smart alarm studies your sleep and wakes you in a light stage with silent vibrations, so a partner is not disturbed. Overnight it measures four sleep stages, disturbances, sleep efficiency and circadian rhythm, along with respiratory rate, SpO2 sampled through the night and skin temperature against your baseline. The Kira assistant explains which parameters affect your sleep. Beyond sleep, Circular lists a single-lead ECG with AFib detection, blood-pressure trends and 14+ health tools in about four grams of titanium. The price is $349 as one purchase with no mandatory subscription, and it is HSA/FSA eligible. Limits: Circular rates battery at 8 days and water resistance at 50m, sizes run about half a size large, and a Circular Ring 3 waitlist is open, so the Ring 2 may be replaced.
Who it is for
People who want a vibrating smart alarm and on-demand ECG in a ring, without a monthly plan.
Price
$349 one purchase; no mandatory subscription; HSA/FSA eligible.
$349 one purchase · no mandatory subscription
Quoted from the vendor pricing page on November 9, 2026.
Key features
- Four-stage sleep: light, deep, REM and awake, with a sleep score
- Silent vibration alarm that wakes you in light sleep
- Respiratory rate, SpO2 through the night and skin temperature versus baseline
- On-demand single-lead ECG with AFib detection, 30-second reading
- Blood-pressure trends and 14+ health tools included
Strengths and weaknesses
- Strength: Vibrating alarm will not wake a partner
- Strength: No mandatory subscription and HSA/FSA eligible
- Strength: 14-day returns and a 1-year warranty
- Weakness: 8 days of battery, shorter than RingConn and Ultrahuman
- Weakness: Sizes run about half a size above standard US sizes
- Weakness: Circular Ring 3 is already on a waitlist
Key facts
- Price: $349
- Battery: 8 days
- Water: 50m
- Weight: About 4g titanium
- Sizes: US 6 to 14
Where it ranks
Circular Ring 2 is No. 7 in our Best Smart Rings verdict.
Alternatives we scored
Visit circular.xyz · Questions or corrections: editorial@hearsmart.org