Yes — and it's coming soon!
We’ve officially announced that the Circular Ring 2 will offer estimates for both blood pressure and blood glucose via a firmware update.
⚠️ Note: These are not medically certified features and are intended for wellness tracking only, not for diagnosis or treatment.
🧠 How Blood Pressure Estimation Works
The Circular Ring 2 is the first smart ring equipped with both a PPG sensor and a single-lead ECG sensor. This powerful combination allows us to estimate blood pressure using a technique called Pulse Transit Time (PTT) — a method widely used in clinical research for trend tracking without a cuff.
Here's how it works:
- The ECG sensor detects the electrical signal of your heartbeat (R-peak).
- The PPG sensor detects the arrival of that pulse at your finger.
- The time delay between those two signals is called Pulse Transit Time (PTT).
- PTT is inversely proportional to your systolic blood pressure.
- Based on this delay, the Circular app calculates an estimated blood pressure value.
🕒 You’ll perform a 60-second spot test to capture this measurement. During the test, you’ll be asked to touch the ring with a finger from your opposite hand to complete the ECG circuit.
🔁 Calibration for Accuracy
To keep estimates accurate, you’ll need to calibrate your ring once per month using a standard cuff-based blood pressure monitor. This step personalizes the measurement based on your cardiovascular profile.
📈 Daily Wellness Insight
Once enabled, Circular will provide a daily estimated blood pressure reading as a wellness indicator — ideal for monitoring lifestyle trends, stress, and recovery patterns.
🧷 FDA Status
We're currently in the regulatory process with our partner for FDA clearance of the blood pressure estimation feature.
🚫 Not a Diagnostic Tool
Please note: These features are not medical devices. They’re meant for informational purposes only and should not be used for medical decisions. Always consult a healthcare professional for clinical evaluations.
Updated on: 23/10/2025