Paris-based smart ring maker Circular announced its next-generation Circular Ring 3 Pro and Circular Ring 3 Slim on September 3, 2026, timed with the opening of IFA 2026 in Berlin. The headline shared by both models is that they are the first Circular rings to combine NFC contactless payments with on-finger vibration alerts. The higher-end Pro adds an electrocardiogram (ECG), blood pressure trend tracking, and non-invasive glucose insights, and its battery life stretches to up to 12 days. Preorders open in December 2026, when pricing will also be announced. Shipments are expected in early 2027.
Health tracking and payments in a single ring
Smart ring makers have long competed on health metrics, but products that also handle payments have been rare. Amaury Kosman, Circular's co-founder and CEO, said payments are a feature every major ring maker has been chasing, and that to the company's knowledge, Circular is the first smart ring in the world to combine payments and health tracking.
Payments use NFC contactless technology and support Visa and Mastercard cards. Think of it as the same tap-to-pay mechanism used by smartphones and smartwatches, moved to the side of a ring. That said, Circular has not yet detailed which countries, regions, banks, or card issuers will be supported, and there has been no announcement regarding payment support or sales in Japan.
The vibration feature marks the return of something that was dropped from the previous Ring 2. Kosman explained that when Ring 2 was developed, the company did not yet have the know-how to fit the newly added ECG circuitry and a vibration motor side by side, and that user feedback pushed the team to make both coexist in Ring 3. The vibrations serve as a silent wake-up alarm, medication reminders, alerts when heart rate or heart rhythm drifts outside the wearer's normal range, and guided breathing cues. Receiving blood pressure or glucose changes as a buzz on the fingertip sets the ring apart from rivals that rely on a phone or watch screen for notifications.
Ring 3 Pro: ECG, blood pressure trends, and non-invasive glucose insights
Ring 3 Pro measures 6.8 mm wide and 2.78 mm thick, and weighs 3 to 4 grams depending on size. That is about 1 mm narrower than the current Ring 2, which is 7.8 mm wide, although at 2.78 mm the Pro is fractionally thicker than Ring 2's 2.65 mm profile. Kosman describes the Pro as broadly the same size as Ring 2. The exterior design carries over the look of Ring 2. On the sensor side, it covers the basics of heart rate, heart rate variability (HRV), blood oxygen (SpO2), skin temperature, sleep, and activity, and adds a single-lead ECG. Circular says its ECG software for detecting signs of atrial fibrillation (AFib) has received FDA clearance.
The Pro also includes blood pressure trend tracking and non-invasive glucose insights estimated from the optical sensor. Circular positions the glucose insights as wellness information for health management, not for diagnosis or treatment. How the values and trends will be presented inside the app has not yet been disclosed.
The other major improvement is battery life. It rises from up to 7 days on Ring 2 to up to 12 days on Ring 3 Pro. Charging is wireless, and pairing the ring with its charging case reportedly adds another 5 to 6 charge cycles on the go.
Ring 3 Slim: dropping the ECG to prioritize thinness and weight
Ring 3 Slim measures 5.9 mm wide and 2.35 mm thick, and weighs 1.9 to 3 grams depending on size, making it a notch smaller and lighter than the Pro. Kosman noted that packing in more features makes a ring larger while the market is moving toward slimmer shapes, and said the Slim removes only the ECG, the single feature that would have made the ring bigger. It keeps the vibration, NFC payments, and core health tracking such as heart rate and sleep. Blood pressure trend tracking stays exclusive to the Pro, while Circular's comparison sheet also lists glucose trend estimates for the Slim. Battery life is up to 10 days, also longer than Ring 2.
The obvious comparison is the Oura Ring 5, released this year. Oura Ring 5 is about 6.09 mm wide and 2.28 mm thick, and Ring 3 Slim lands close to those dimensions. Keeping health tracking running while looking like slender jewelry has become a shared direction across the smart ring industry, and Circular is falling in line with it.
Both models use a titanium-based metal body and are water resistant to 5 ATM (equivalent to a depth of 50 meters). Sizes run from US 6 to 14, and the four colors are Gold, Silver, Rose Gold, and Black, the same lineup as Ring 2. The app supports iOS and Android, and Kira, the AI assistant inside the app, explains the measured data in plain language.
On pricing, Kosman stated clearly that the ring's core functions will remain usable without a subscription, as before. However, the newly added blood pressure and glucose features will fall under an optional paid subscription that users choose to join. The specific subscription terms are expected to be published together with pricing when preorders open in December. For reference, the current Ring 2 sells for 299 USD (about 46,000 yen) on the official site, also with no forced monthly fee. ※1 USD = 155 JPY
Rivals and remaining questions
2026 has been a year in which competition in the smart ring market intensified sharply. Oura Ring 5 and RingConn Gen 3 arrived in quick succession, and SAMSUNG has confirmed that a Galaxy Ring 2 is coming. Oura handles glucose by pairing with a separately sold Dexcom sensor, and RingConn Gen 3 offers vibration alerts, so rivals overlap on parts of the package, but no product yet bundles payments, vibration, ECG, and glucose insights in a single ring.
Circular also has hurdles to clear. Reviews of Ring 2 by overseas media pointed to the reliability of app syncing and the polish of its features rather than the hardware, so software improvements will likely shape how Ring 3 is received. In addition, cuffless blood pressure tracking via optical sensors has only recently reached practical use even among large players, with Apple starting hypertension notifications on its watch. How reliable the trends will be in a ring form factor will be tested once units ship. With preorders in December and shipping in early 2027, there is still some time before the rings reach customers' hands.
Summary
Ring 3 Pro and Ring 3 Slim, announced by Circular at IFA 2026, are smart rings that share NFC payments and vibration alerts, with the Pro adding ECG, blood pressure trends, and non-invasive glucose insights. Battery life is up to 12 days on the Pro and up to 10 days on the Slim, a big jump from the previous model's 7 days. The ring's core functions require no subscription, but the blood pressure and glucose features come under an optional paid subscription. Preorders and pricing arrive in December 2026, shipping is slated for early 2027, and availability in Japan has not been announced.
