Circular Announces Ring 3 Series with NFC Payments, Split into Pro and Slim Models
Circular has announced its Ring 3 Series, the follow-up to the Ring 2 that debuted at CES 2025. The lineup splits into two models: the Pro, which keeps the health-tracking features of its predecessor, and a slimmer, lighter Slim variant. Both are expected in early 2027, with pricing yet to be disclosed The Verge.
Both the Pro and Slim integrate NFC (near-field communication) chips for contactless payments, letting wearers pay by tapping their ring against a terminal, no phone or wallet required. The rings also feature vibrating haptic alerts for alarms, medication reminders, and guided breathing exercises The Verge. The idea is that a ring is something people will keep on through sleep, showers, and workouts, which gives the optical sensors inside the best chance to capture clean data Circular.
The Ring 3 Pro builds both its inner and outer structures from titanium for durability and comes in gold, rose gold, silver, and black finishes. Battery life on the Pro has been extended from the previous generation's seven days to up to 12 days, achieved despite a smaller capacity battery. Its wireless charging case can top off the ring five to six times before the case itself needs plugging in The Verge.
The Pro carries forward the Ring 2's core health-tracking features, including upgraded sensors and FDA-cleared atrial fibrillation detection. The FDA clearance is documented in 510(k) Premarket Notification K221361, filed by applicant Bodimetrics under regulation number 870.2700 FDA. Atrial fibrillation, or AFib, is an irregular heart rhythm that can increase stroke risk. The device takes an ECG (electrocardiogram) reading from finger to finger in about forty seconds and flags signs of AFib Circular. Circular markets its Ring 2 as the world's first smart ring with ECG and AFib detection Circular.
The Ring 3 Slim takes a different hardware approach. It is slimmer, thinner, and lighter than the Pro and delivers up to 10 days of battery life. Instead of titanium, the Slim uses a nonmetallic material Circular calls a "biocompatible epoxy" on the inside of the ring. It relies on PPG (photoplethysmography) sensors, which use light to measure blood flow, for heart rate and blood oxygen (SpO2) levels, but it omits the ECG sensor and AFib detection found in the Pro The Verge.
Both Ring 3 models track skin temperature, daily activities, sleep, and heart rate variability (HRV), which measures the variation in time between heartbeats and can indicate stress or recovery levels. The PPG optical array samples heart rate, HRV, and blood oxygen continuously through the night. Skin temperature is measured as a deviation from the wearer's own baseline, which the company describes as an early signal of illness or a menstrual cycle phase. A three-axis motion sensor tracks sleep stages, workouts, and steps without manual input. The haptic engine provides a silent alarm felt on the finger, not heard by others in the room The Verge Circular.
CNET published its coverage of the Circular Ring 3 Pro and Slim on September 2, 2026, reporting that the models add NFC payments and haptic feedback CNET. The Verge followed with its reporting on September 3, 2026.
The broader context here is a smart ring market navigating the tradeoffs between continuous biometric monitoring and form factor constraints. Adding NFC moves the ring beyond passive data collection into active daily utility, a progression we watched play out in smartwatches roughly a decade ago. The split into Pro and Slim hardware tiers suggests manufacturers are recognizing that sensor density and battery capacity dictate the physical footprint of these devices.
Worth flagging is the Pro's battery jump from seven to 12 days alongside a smaller capacity cell. If that figure holds in independent testing, the power management implications are notable for a device packing an ECG sensor, continuous PPG sampling, and an NFC radio into a titanium chassis. The Slim's removal of the ECG sensor to achieve a thinner profile indicates that clinical-grade diagnostics remain the primary constraint on how small these wearables can get.
In this author's view, the deliberate split of the lineup is a pragmatic response to adoption barriers. Stripping the Slim down to PPG basics and a biocompatible epoxy interior lowers the entry threshold for users primarily interested in sleep and activity tracking, while the Pro retains the regulatory clearances and durable materials necessary for users focused on cardiac metrics. What this ultimately enables is a wider on-ramp for finger-based biometric sensing, a category that has struggled to balance clinical utility with the form factor necessary for true 24/7 wear.
