French startup Circular claims to have developed the world’s thinnest and lightest smart ring, known as the Circular Ring Slim, which is now available for pre-order. Weighing just 2 grams and measuring 2.2 mm in thickness, the ring offers a range of features packed into a compact design. The device is equipped with sensors that analyze seven biometrics and 142 derived markers to assess the user’s health.
Key sensors include a surface temperature sensor, a three-axis accelerometer for activity and movement assessment, and photo-plethysmo-graphy (PPG) sensors utilizing green, red, and infrared LED light wavelengths. The PPG sensors capture health vitals such as heart rate, respiratory rate, and blood oxygen levels. During sleep, the ring tracks indicators of sleep quality, including REM cycles, wake times, and temperature variations.
Circular’s AI assistant, Kira+, processes the collected data and provides insights and advice. The company emphasizes the system’s accuracy, stating that the ring is used in clinics and scientific studies with a focus on data accuracy.
The smart ring boasts a six-day battery life, 20 days of onboard memory, and data collection every two minutes, claiming to offer 15 times more health data than competitive trackers. It also introduces haptic navigation, allowing users to tap inputs for various functions and experience haptic vibrations for feedback and alerts — These vibrations support features such as a smart alarm clock, waking users at an optimal time in their sleep cycles.
Circular aims to compete in the wearables market, envisioning smart rings (like Mota, Ring One, and Oura) as increasingly popular due to their comfort, durability, longer battery life, and compatibility with traditional watches. The Circular Ring is available for pre-order at a discounted price of $245 (€226), with shipments scheduled for December 15, after which the device will be priced at $275 (€253). Orders can be placed on the Circular website.