Circular today announces the Circular Ring 2, the first and only smart ring capable of recording a clinical-quality electrocardiogram (ECG) directly from your finger.

Until now, ECG readings required a chest strap, a smartwatch, or a visit to the doctor. The Circular Ring 2 changes that: touch the ring with your opposite index finger for 45 seconds, and it records a single-lead ECG that analyzes your heart rhythm for irregularities.

How it works. The ring's surface contains actual ECG electrodes. When you complete the circuit by touching the ring with your opposite hand, it measures the electrical signals that trigger each heartbeat — the same principle as a hospital ECG. The onboard algorithm analyzes your heart rhythm and flags signs of atrial fibrillation (AFib), the leading cause of stroke, which often goes undetected until it is too late.

Why it matters. This is the first time a smart ring has offered ECG-based heart rhythm analysis. Unlike a watch that you charge every night, or a chest strap you would never wear to dinner, the Circular Ring 2 is on your finger 24/7. That means you can check your heart rhythm anytime, anywhere.

The Circular Ring 2 also includes continuous SpO2 monitoring, sleep stage tracking, HRV analysis, respiratory rate, body temperature, and Kira AI coaching — all in a 2-gram titanium ring with up to 7 days of battery life. No subscription.

Available now at shop.circular.xyz.