10+
Industry Awards

Health tracking through the first medical-grade ECG smart ring

Precision in Every Detail,

Clarity in Every Insight

Clear and actionable recommendations from Kira, your AI health coach—analyzing 140+ biomarkers that turn your data into action.

Meet the Circles
13+ features, no subscription 

Experience the Finest Craftsmanship
in our most Luxurious Smart Ring

Sleek, sophisticated, and built to last

Expertly crafted like fine jewelry, Circular Ring 2 is both elegant and sleek. Made from premium titanium, it weighs just 2 grams—offering an unrivaled balance of strength and lightness for all-day comfort.

Perfect fit, zero hassle

Our precise digital sizing tool ensures a perfect fit in seconds—straight from your phone. No delays, no excess packaging, just effortless accuracy.

Kira: Turning Deep Health Data into smart action

An AI-powered personal health strategist that suggests exact actions to make you healthier. Kira analyzes 140+ biomarkers daily to deliver real-time, science-backed insights.

Kira

01/03

Put a ring
on it

Get the most powerful health tracker today. No subscription. New features evolve with over-the-air updates.

02/03

Join The
Community

Download the Circular app, your personal hub providing for all things health and life improvement related. From sleep, energy, stress, heart issues and more.

03/03

Earn

Benefits

Circular calibrates your body and mind for the best insights possible from Kira, your personal AI wellness assistant. Watch the data roll in, grow as a person, and elevate your life by unlocking real-life benefits with your hard-earned Circular coins.

What Circular analyzes for you

Blood oxygenation

Blood oxygen level (SpO2) is a measure of how much oxygen your red blood cells are carrying. Maintaining a precise balance of oxygen-saturated blood is vital to your health. SpO2 is a valuable metric as it is closely related to a lot of respiratory conditions (shortness of breath, asthma, sleep apnea, and more…). A normal reading is typically between 94 and 100 percent. Monitoring blood oxygen level can help with prevention, altitude acclimatisation, recovery and determining if treatments are working.

Heart rate variability

Heart rate variability (HRV) measures the specific changes in time between successive heartbeats and is a great measure of your autonomic nervous system. It can unveil many things about your overall wellbeing. It is used to see how well you recovered after certain events and is a good measure of general stress and tiredness. Variations of HRV are measured against your own Reference. Anything above means that your body and immune system are ready to tackle the upcoming day whereas the contrary would probably mean that you need to focus on recovering.

Temperature variation

Temperature variation is an essential metric to evaluate how your natural defenses respond to your environment. When the variation is higher than +/- 0.8 degrees Celsius compared to your usual baseline, that’s when you need to start paying attention. It can fluctuate with activity, your nutrition, your circadian rhythm, can indicate that your body fights against an illness, can reflect external environment changes such as a season change and can reflect a woman’s menstrual cycle.

Heart rate

Heart rate is the basis of many measurements at Circular. With continuous heart rate monitoring you can get a comprehensive view on how your heart rate change in response to your activities and emotions. In addition to tracking your bpm continuously, we derive many other very valuable metrics from it. A great benefit of having a device like the Circular ring on your finger is that it is most likely one of the most optimal places for PPG-based tracking making measurement more reliable and accurate.

Energy

This is the ultimate score that tells you how much energy you have accumulated for the day. It is made up of many day and night contributors that evaluate your vitality. Every aspect of your body is considered whether it is the immune system, stress levels, sleep, or activity recuperation. If the energy score is high it means that you can surpass yourself, do intense activities, intense mental activities while having minimal risks of getting sick. If it’s low, don’t push yourself, your immune system is weak, avoid over-training and focus on rest.

Activity intensities and calories burned

The Circular ring continuously monitors your activities. Activity intensities are used to quantify whether you do enough physical activity according to your needs and the scientific literature. For ease of reading your activities are divided into low, medium, and high intensity activities. Thanks to these, Circular can determine for you, your active minutes, training zone, activity volume, recovery time and calories burned. Circular correlates the data to determine the type of activity (e.g. running, biking, swimming).

Steps

Circular continuously determines whether you are walking or running and counts for you the number of steps. It also estimates the walking distance equivalency. Circular sets goals by analyzing your profile and habits and helps you achieve your walking goals.

Resting heart rate

RHR is a great measure for your overall health, readiness, and fitness. A low RHR is an indication of a strong heart muscle that can pump out a greater amount of blood with every beat, so it does not have to beat as frequently. Generally speaking, the lower it is, the better. A higher RHR compared to your Reference indicates poor overall wellness conditions, this means that you should avoid too much physical stress and concentrate on recovering.

Breathing rate

Breathing rate reported in breaths per minute is an indicator of your cardiovascular load and is a good indicator of your wellbeing. You breathe harder and faster when you are ill or in need of energy. This metric varies much less than your RHR and HRV. It becomes very useful when it evolves a lot compared to your Reference. This metric acts as a threshold when something is highly unusual. A normal reading for a resting adult ranges from 12 to 18 breaths per minute.

Vo2 max

VO2 max represents the maximum oxygen flow that the body can consume during an effort. VO2 max is considered as a criterion for evaluating physical performance. It gives an indication of the level of fitness and endurance. The higher the value, the more it is easy to maintain an effort of a certain intensity over time. By increasing your VO2 max with training, you will be able to run either faster for the same distance or longer for the same intensity.

Sleep cycles

While  sleeping, you go through several successive stages that all have different functions for your body and mind recovery. Circular automatically tracks your sleep stages (Awake, Light, Rem and Deep sleep), deduces your chronotype, detects your sleep cycle length, assesses how you respond to your current sleep schedule by analyzing several tracked biometrics and parameters that reflect your sleep quality, energy levels, your time to fall asleep, your activities, etc. The goal is to recommend you the perfect duration you need to sleep and how to improve your sleep quality.

Arrhythmia

Circular analyzes your heart rhythm and flags any irregularities that might occur. AFib is a type of arrhythmia which is a condition characterized by an irregular and often rapid heart rate. This irregularity arises from chaotic electrical signals in the heart.Arrhythmia, if not treated, can damage the heart, brain, or other organs. aFib can potentially lead to stroke or heart failure. Early detection and management of arrhythmia are vitals to maintain health over the long term.

Stress

Stress can make you lose your composure, but with Circular, you can quantify your stress levels throughout the day. Experience the power of stress analysis seamlessly connected to your personal notes. Plus, with predictions for the upcoming hours, you can proactively plan your day, ensuring that it's not just productive, but also emotionally balanced. This unique combination equips you with actionable insights, making stress a thing of the past. It's like having a digital mentor, guiding you towards a more balanced and fulfilling life.

Coherence

Elevate your emotional state in the moment so you feel better and think more clearly.  The coherence score measures and translates your heart rhythm patterns (HRV) into real-time a coherence score. This trains you to get your heart and brain in sync, which prevents and reduces stress, anxiety, and improves health and performance for more effective choices. With just a few minutes of daily practice, coherence state becomes easily accessible.