Circular's digital sizing may have solved smart rings' biggest pain point

French tech brand Circular is stepping up its smart ring game with the unveiling of its Circular Ring 2, the brand announced on Sunday at the Consumer Electronics Show in Las Vegas.

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The second-generation smart ring is all-in on heart health monitoring and upgrades many of its features to keep up with the industry competition. There's an FDA-cleared Atrial Fibrillation detection algorithm to monitor arrhythmia included within the ECG capability for "real-time heart health insights," according to the press release, and improved sensors that reportedly boost the accuracy of data captured.

Most smart ring brands send customers a ring sizing kit to try on the correct ring size before committing to a smart ring. Circular is changing this process with its Digital Ring Sizing, which users can try out on their phones -- no physical kit is needed. The Digital Ring Sizing uses a smartphone's camera to determine a user's ring size. This is the first smart ring brand, to our knowledge, that uses a smartphone camera for ring sizing.

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Circular extends the new smart ring's battery life to eight days, compared to the six-day battery life of its Circular Ring Slim. This battery life extension is on par with other smart rings in the space, like the Oura Ring 4. The app will also get a redesign for a more "intuitive and refined" look and user experience.

The titanium-built Circular Ring 2 comes in four new finishes, including gold, silver, black, and rose gold, a step up from the earlier generation's two finishes of silver and black. The Circular Ring 2 is expected to be available around February or March of 2025 for $380.