Just in time for CES 2025, Circular has lifted the curtain to reveal the new Circular Ring 2, a completely redesigned smart ring that offers two key features that no other smart ring, including the Oura Ring, can match. These include on-finger ECG readings with FDA-cleared atrial fibrillation (AFib) detection and a potentially revolutionary new digital sizing process.
The Circular Ring 2 is set to arrive in four finishes this spring boasting specs and a starting price comparable to the best smart rings available in 2025. Here's everything you need to know about the new Circular Ring 2.
Circular Ring 2: price and availability
Announced on January 5th, 2025, the Circular Ring 2 is expected to launch via a crowd-funding campaign in mid-to-late January before shipping in March with a starting price of $349, the same as the Oura Ring 4; but unlike Oura, the Circular Ring is subscription-free.
Perhaps a more direct competitor, price-wise, is the Samsung Galaxy Ring, which is also subscription-free, and costs $399.
No word yet on sizes but 2023's Circular Ring Slim is available in sizes six through 13 — and your choice of a black or silver finish — and it's safe to assume that the Circular Ring 2 will be available in a similar range of dimensions.
The Circular Ring 2 will also ship in two new finishes, gold and rose gold, as well as silver and black.
Circular Ring 2: design and key features
The Circular Ring 2 has been completely redesigned. While the Circular Ring Slim is made from a mix of materials, including aluminum, titanium and unspecified non-metal material on the inside, the new Circular Ring 2 has an all-titanium exterior.
The Slim is notoriously easy to scratch — just ask our colleagues at Tech Radar — so, I'm hopeful this shift in materials will lead to a more durable outer surface on the Circular Ring 2.
The Circular Ring 2's environmental sealing rating has been slightly increased over the Ring Slim, from IPX8 to IP68. This still isn't quite enough water resistance for swimming but it should be enough for hand washing and showering.
In addition to the exterior redesign, the Circular Ring 2 boasts new sensors for better holistic tracking accuracy. More importantly, the Ring 2 is officially one of the first smart rings on the market promising on-finger ECG readings to monitor heart health, along with FDA-approved AFib detection.
Neither the Oura Ring 4 nor the Samsung Galaxy Ring support ECG readings or AFib detection via the finger, but plenty of Samsung smartwatches, including the latest Galaxy Watch 7 and Galaxy Watch Ultra, do.
Circular Ring 2: battery life and charging case
One of our most notable complaints about the Circular Ring Slim is its unimpressive battery life, averaging just two days of use per charge. However, the new Circular Ring 2 touts a whopping eight days of life per charge. And that's with 24/7 health and sleep monitoring.
This level of longevity puts the Ring 2 in the same camp as the Oura Ring 4 and Samsung Galaxy Ring. The Circular Ring 2 also ships with a new wireless charging dock, which sounds similar in concept to what you get with the Galaxy Ring (a dock we like very much).
Circular Ring 2: updated sizing process and app
One of my greatest frustrations about smart rings in 2025 is how tedious the sizing process tends to be. Even if you know your ring size, smart ring sizing marches to the beat of its own drum and varies from brand to brand.
While the big players, including Samsung and Oura, still recommend customers buy a $10 sizing kit before purchasing their smart ring, Circular is taking a more earth-friendly approach to smart ring sizing.
Digital Ring Sizing is a new feature coming to Circular's companion app that presumably uses your camera to get an exact ring size measurement, saving you the hassle of ordering, waiting for, using, and tossing out a superfluous kit before committing to a ring.
The companion app has also been redesigned to make navigation easier.
Circular Ring 2: outlook
I haven't had a chance to try the Circular Ring Slim but its quirks are fairly well documented, particularly by my colleague, Sam Hopes, who initially loved the device, but ultimately ditched it in favor of her Oura Ring 3. Her biggest qualms: a less-than-comfy design that scratches too easily, a confusing app with spotty data transfer reliability and unimpressive battery life.
The Circular Ring 2 seemingly addresses each of these pain points, and then some. And if it fully delivers in the battery life, durability, usability and reliability departments then it could very well be the subscription-free, smartphone OS-agnostic alternative to the Oura Ring 4 and Samsung Galaxy Ring that the people deserve.
In fact, if the Circular Ring 2 lives up to its billing and the ECG and AFib detection features work reliably, Circular could very well steal Oura's crown as the smart ring manufacturer to beat in 2025.
I'll be checking out the new Circular Ring 2 in person at CES 2025 this week and look forward to sharing my hands-on experience and initial impressions in the coming days.
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