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4.5
Circular Ring 2 combines a jewelry design with tracking of 140+ biosignals across 13+ health features — including ECG, AI coaching, sleep, activity, recovery and more. A health lab on your finger, with a subscription-free experience and premium features like blood pressure and glucose trend coming soon.
Clinical-level ECG & AFib Detection
On-demand heart rhythm monitoring.
Kira™ AI Health Coach
Actionable insights and wellness suggestions tailored to your body.
No Subscription Fees
All vital features included. No hidden costs.
Pick your color
Pick your size
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Or don't know your size?
Buy with Sizing Kit
Extra Peace of Mind?
yearly
Extra protection. Covers accidental damage and full replacement. One per ring.
Better sleep quality
Enhance your recovery and sleep quality with the ultra-soft Circular Sleep Mask.
Extra Charger
Add a supplimentary charger to your order. Pick the same size as your ring.
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Features
Blood Pressure Monitoring
Track your blood pressure trends. Understand how stress,
sleep, and activity affect your heart health over time.
Coming as a premium feature in early 2026.
Glucose Trend Monitoring
Stay ahead of your blood sugar fluctuations with non-invasive tracking. Ideal for those managing energy levels, metabolism, or early glucose sensitivity. Planned for mid 2026, as a premium feature.
ECG + AFib Detection
Track your heart rhythm with world’s first medical-grade technology and catch signs of arrhythmia before symptoms appear.
Sleep Tracking
Monitor sleep stages, breathing, and oxygen levels to understand how well your body recovers overnight.
Women’s Health
Keep track of your cycle, hormonal shifts, and fertility with personalized insights based on your vitals.
Stress & Energy Monitoring
See how stress affects your body and get guidance on when to rest or push harder.
Advanced analytics
Make graphs overlap and understand how different metrics are linked.
Energy monitoring
Get stats and in depth insights about your energy levels.
Live measurement
On-demand spot measurement for HR, SpO2, HRV, activity intensities, and Max HR.
Alarm clock
Wakes you up with a smart alarm during your lightest sleep stage with your phone's vibrations.
Guided breathing
Launch guided breathing exercises to relax, sleep better, and more.
Vital alerts
Get notified when you vitals are going off.
Medication
Never forget to take your meds anymore and keep track of your intakes.
Coherence
Dive into a state of optimal function and regulate your emotions and clarity.
Sport Sessions
Track outdoor activities with a GPS trace and reports.
Airplane Mode
Disable ring’s Bluetooth communication.
Timer
Set a timer for your workout or anything else.
Calendar
Add manual notes that are reflected in the app and add context to your data.
Heart Rate + HRV
24/7 heart rate & morning resting heart rate and heart rate variability.
Breathing Rate
Breathing rate during sleep periods.
Blood oxygenation
Medical grade SpO2 levels during sleep & rest periods.
Temperature
Temperature variations trends help detect fever, menstrual cycles.
Kira™ Coaching
Your AI health coach turns complex data into clear, actionable tips tailored to your lifestyle.
Battery & Charging
Wear it for up to 8 days straight. Then wirelessly recharge in just 30 minutes.
What's in the box?
Circular Ring 2
Wireless Charging Case
USB-C cable
Cleaning Cloth
App Access
Digital User Guide
Technical Specs
2.55mm thick, 7.8mm wide, 3 grams
Sizes: US 6–14
Battery: 8 days (Power Mode), 5 days (Performance)
Charging: 30 mins via wireless charger
ECG, PPG, temp sensor, 3x accelerometer
Bluetooth Low Energy, Airplane Mode
iOS & Android compatible
GDPR & HIPAA compliant
Because
Premium
Means
Protected
Free Worldwide Shipping
for any non-discounted order
Free 14-Day Return
1-Year Warranty
24/7 Support
Free Worldwide Shipping
for orders >$349
Free 14-Day Return
1-Year Warranty
24/7 Support
13+ Advanced
Health
Features
Every key signal your body gives — tracked, analyzed, and translated into real guidance.
Designed Not to Distract
No lights, no buzzes, just a luxury ring that fits seamlessly into your daily life with no distractions.
Battery & Charging
Wear it for up to 8 days straight. Then wirelessly recharge in just 30 minutes.
The Case That Powers Your Ring
Your ring comes with its own sleek charging case. It protects, powers, and extends durability without the need to plug in.
You wear the ring. The app listens.
Kira
responds.
The ring captures over 8 key health signals and the app turns those readings into clear, easy to understand insights. You see patterns in your recovery, energy, stress, and sleep without needing to decode anything.
And then, Kira, your AI health coach, watches for any changes in your vitals, spots early warning signs, and sends you gentle, helpful recommendations. No searching. No guessing. Kira already knows what matters and what to do next.
Technical Specs
2.55mm thick, 7.8mm wide, 3 grams
Sizes: US 6–14
Fully Waterproof
Withstands daily use in the shower, pool, or rain
Battery: 7 days
8 days (Power Mode), 5 days (Performance)
Charging: 30 mins via wireless charger
ECG, PPG, temp sensor, 3x accelerometer
Bluetooth Low Energy, Airplane Mode
iOS & Android compatible
GDPR & HIPAA compliant
Titanium body, hypoallergenic interior
Finished with a durable PVD coating protecting it from scratches and wear.
Titanium body, hypoallergenic interior
Finished with a durable PVD coating protecting it from scratches and wear.
Trusted by People Who
Live Well
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color
What people say about
Circular?
Blood Pressure & Glucose is a dream
4.9
I'm super happy about the features, looking forward to wearing this. I'm super excited for Blood pressure and Glucose. It's crazy that you can do that with such a small technology.
Designed not to distract
4.9
No screen, no buzzes, just a stylish ring that fits seamlessly into my daily life with no distractions.
EKG is a nice addition!
4.9
As a cardiology professional (hospital turned med tech), of 19 years, the EKG feature is the one I cannot wait for!! Exactly what I've been waiting for.
What’s in the
Box
Circular Ring 2
Wireless Charging Case
USB-C cable
Cleaning Cloth
App Access
FAQ
What makes Circular Ring 2 different from other smart rings?
Circular Ring 2 combines industry-leading accuracy with a lightweight titanium design. It measures over 13+ health features and 140+ biometrics, with data updating up to two minutes. Unlike trackers that only show numbers, Circular pairs data with Kira, your personal AI health coach, who translates trends into simple, actionable advice. See Circular experience as a health lab at your finger.
Does Circular Ring 2 require a subscription?
No. All 13+ health core features and 140+ biometrics are free forever. Only a small number of premium features use a freemium model (free & paid part with coins or money).
All the core features are free, with no subscription required. These include:
ECG (40-second heart rhythm check)
Sleep tracking (including sleep stages)
Energy trackingSmart Alarm (with phone's vibration)
Vital alerts for irregular changes
Guided breathing sessions
Stress tracking & predictions
Chronotype analysis
Women’s health tracking (cycle, fertility, hormonal phases)
24/7 activity tracking and sport sessions
HRV (Heart Rate Variability) monitoring
Skin temperature trends
Blood oxygenation (SpO2) during rest and sleep
Live measurement of HRV and heart rate
Personalized wellness recommendations
Immunity index and medication reminders
Coherence (emotional regulation training)
Premium features are available in two ways:Pay directly (classic premium subscription).
Use Circular Coins (earned by daily use of your ring).
Premium features include:Blood pressure (two-tier model: free score & detailed trends + premium)
Blood glucose trend (coming 2026)
How to wear the Circular Ring?
You can wear Circular on any finger. To find your size, please read our different sizing options.
What are Circular Coins?
Circular Coins are our way of rewarding you for staying consistent and improving your health.
You earn coins by using your ring daily.
You can use them to unlock premium features and real-life benefits.
No crypto, no trading — just loyalty rewards inside the app.
Current users will have time to collect coins before premium features launch.
How does blood pressure tracking work?
Circular Ring 2 is the first smart ring equipped with both PPG (photoplethysmography) and a single-lead ECG sensor, enabling blood pressure estimation.
Circular Ring 2 uses a technique called Pulse Transit Time (PTT) to estimate blood pressure. This method is commonly used in clinical research to track blood pressure trends without a cuff.
How it works:
The ECG sensor detects the electrical signal of a heartbeat (R-peak).
The PPG sensor detects the arrival of the pulse at the finger.
The time delay between these two events is known as Pulse Transit Time (PTT).
PTT is inversely proportional to systolic blood pressure.
Based on this delay, Circular calculates an estimated blood pressure value.
To enhance accuracy, users must perform a calibration using a traditional blood pressure monitor once every month.
Blood pressure measurement is done via a 60-second spot test, during which the user is required to touch the ring with a finger from the opposite hand to activate the ECG and complete the circuit.
Circular provides a daily blood pressure estimate as a wellness indicator, perfect for tracking trends related to stress, recovery, and lifestyle.
Not a diagnostic tool. This feature offers informational wellness guidance only and should not replace clinical evaluation.
We designed a two-tier blood pressure feature:
Free version: a simple, color-coded BP score for quick daily insights.
Premium version: detailed numbers, graphs, and Kira’s context, showing how BP relates to your sleep, stress, and activity trends.
This hybrid model keeps essentials free while covering the costs of advanced algorithms and cloud processing required for in-depth analysis.
How accurate is the data?
Circular Ring 2 uses industry-leading sensors and algorithms, tested against gold-standard equipment. Updates every two minutes ensure both precision and responsiveness, whether you’re resting or active.
What is Kira, and how does she help me?
Kira is your personal AI health coach inside the app. She:
Translates your vitals into clear, simple recommendations.
Spots early warning signs before you notice them.
Helps you understand patterns in sleep, stress, recovery, and energy.
Learns your body during a short calibration period (about 14 days) to tailor insights to you.
Is the ring waterproof?
Yes. Circular Ring 2 is fully waterproof, safe for swimming, showering, and daily wear.
What is the ring made of?
The outer body is crafted from ultra-light titanium with a PVD coating (for premium finishes like gold and rose gold). The interior is hypoallergenic, safe for sensitive skin, and designed for comfort 24/7.
How long does the battery last?
A quick 30-minute charge gives you up to 8 days of use. Actual battery life depends on how you use the ring:
Power mode (all-day tracking + nightly sleep tracking): around 7-8 days.
Performance mode (high-frequency measurements, workouts): around 4-5 days.
Where can I see my data?
All insights are available in the Circular app (iOS and Android). You’ll see clear graphs, scores, and personalized recommendations.
Is my data secure?
Yes. Your data belongs to you.
Protected with end-to-end encryption from ring to app to cloud.
Stored and processed on secure servers that comply with strict European and international standards (like GDPR).
You can delete your data anytime in the app.
We never sell or share your health data.
When will new features like blood pressure and glucose tracking be available?
Blood Pressure: rolling out by the end of 2025.
Blood Glucose: planned for early 2026.
All other features are available instantly.
Can I travel with Circular Ring 2?
Yes. The ring is airplane-safe and meets all global certifications. It even includes an airplane mode to turn off Bluetooth while still collecting data.
How does the ECG feature work?
You can take a 40-second ECG anytime, anywhere. It records your heart rhythm and gives you a reliable snapshot of your heart’s electrical activity. Results appear instantly in the app, and you can export and share your results in PDF format.
Can Circular Ring 2 track stress?
Yes. Stress levels are estimated through heart rate variability (HRV) and other vitals. Kira then helps you see what might be driving your stress and suggests practical breathing or recovery techniques to bring balance back.
What is the Energy Score?
The Energy Score combines data from your sleep, recovery, and activity into one simple measure. It shows when you’re ready to perform and when it’s better to slow down.
How does the smart alarm work?
The smart alarm tracks your sleep cycles and wakes you during your lightest sleep stage, with your phone's sound, so you start the day feeling refreshed instead of groggy.
Can the ring track my workouts?
Yes. Circular Ring 2 automatically tracks your daily activity and supports manual sport sessions with GPS. It monitors workout intensity, heart rate zones, calories — so you know if your training is paying off.
How does sleep tracking work?
The ring tracks your sleep in detail, including total duration and deep, light, and REM stages. It also monitors your breathing rate, heart rhythm, and SpO₂ overnight. After the short calibration period, you’ll start receiving a Sleep Score and clear sleep trends.
Does the ring monitor my breathing?
Yes. Circular Ring 2 records your breathing rate during sleep. This helps highlight recovery quality, altitude adaptation, or unusual patterns that may affect your rest.
What about body temperature?
The ring tracks skin temperature trends. This can help identify fever, monitor recovery, and provide insights into menstrual cycle phases or hormonal shifts.
Can it help with women’s health?
Yes. Women’s health tracking is built in. It monitors your cycle, fertility windows, and hormonal phases using your body’s signals, not just calendar predictions.
How does blood oxygen tracking help me?
Circular Ring 2 measures SpO₂ levels during sleep and rest. This shows how well your body is oxygenated, which is important for sleep quality, altitude changes, and overall recovery.
What are Vital Alerts?
If something unusual happens in your vitals — such as a sudden heart rate spike or drop — Circular sends a Vital Alert. These phones' notifications help you log, keep a history, and catch changes early so you can take action.
What is Coherence training?
Coherence is a guided practice for emotional clarity and calmness. It helps you regulate your breathing and heart rhythm, making it easier to manage stress and improve focus.
Can I get personalized recommendations?
Yes. Beyond raw numbers, Kira connects the dots across your sleep, stress, recovery, and activity. She translates them into clear, tailored steps that fit your lifestyle.
Does the ring remind me about medication?
Yes. You can set up medication reminders in the app to track your medication intakes. Subtle notifications from your phone's vibration help you stay on track without disrupting your day.
Complete Your Experience
A little extra goes a long way.
- WWayneVerified ReviewerRated 4 out of 5 stars1 week agoGood but definitely could be better
Although I generally am pretty happy with the ring, I do have some issues.
1. It is easily marked up. I have only had it a few months and it is already pretty scratched up. See below.
2. There have been quite a few instances when the ring did not record steps. I would like to see a capability to edit steps - not goals, actual steps. That way steps recorded on a treadmill while holding handrails (necessary for us seniors) and step equivalents from stationary bike riding, could be added.
3. We still don't have blood pressure monitoring which was promised by end of 2025, and no indication as to when it will be available.
4. There are almost too many graphs/metrics! I regularly use the sleep and energy circles and occasionally the heart rhythm circle, but not so much the rest. I would also like to edit the vitals targets: I am getting alerts multiple times a day for bpm over 90, even though the recognized norm is between 60-100. Way too many meaningless alerts. use the norm at least, or give us the option to edit the targets.
CCircular1 week agoHello Wayne,
Thank you so much for your feedback! Regarding steps, you’re right, if you hold handrails, the ring unfortunately won’t count those steps, but we really appreciate your suggestion.
As for your vitals targets, you can absolutely edit them to adjust alerts above 90 bpm. Just go to Vital Alerts, tap the small purple button at the bottom right, and select Edit Trigger. This way, you can customize your alerts to better match your personal targets.
- CUClemens U.Verified ReviewerRated 4 out of 5 stars1 month agoGood Ring - buggy Software - a startup ;-)
I got the Ring 5 Weeks ago. Shipping takes Long but its worth waiting for it (sitting Kit - 4! Weeks shipping ;-() the app to size was one size off (smaller)
Hardware is super slick - and can be worn under gloves for Sport.
Seems Sync is finally under More Control - i lost a good piece of data because of Sync issues, especially when travelling across timezones ;-( I Hope this is fixed now.
One can see that its a startup that scales currently,.. support inquires take 2 weeks for an answer and are often insufficiently answerer - i guess the poor guys are overwhelmed sometimes.
Apple Health Integration is ok, its a Small Set of what could be Done (age, gender,… all missing).
I am hoping Sugar and blood pressure to come soon - this was the reason to but the Ring in the First Place.
The biggest Problem with it - is its Software Design - if You are not online - there is a Lot of data missing in the app, because its designed for always online.
CCircular1 month agoHi Clemens,
Thank you for sharing such detailed feedback, and we really appreciate your patience and support.We’re glad to hear you like the hardware! We understand the sync issues, these are linked to recent server problems, which should be fully resolved very soon.
We also hear your feedback on app design, Apple Health integration, and the features you’d like to see added. Our team is actively working on improvements and premium features like blood pressure tracking and blood glucose trend monitoring, stay tuned!
Thank you again for your patience and for supporting us while we scale as a startup. We’re committed to making the app and ring experience as smooth and reliable as possible.
- LLauraRated 5 out of 5 stars2 months agoMy favorite piece of smart jewelry
I absolutely love my Circular Ring 2 — it’s sleek, comfortable, and matches all my outfits. I first bought it for fitness tracking, but now I’m obsessed with checking my sleep and recovery stats every morning.
- ELEmma L.Rated 5 out of 5 stars2 months agoStylish, smart, and surprisingly addictive
I started wearing the Circular Ring 2 just for sleep tracking, but now I never take it off. It looks elegant with any outfit and feels so light you forget it’s there. The insights on recovery and stress are super helpful — I even got one for my sister because she kept borrowing mine!
- ZMZoe M.Rated 5 out of 5 stars2 months agoNice balance of tech and style
I love how elegant it looks. In love with this color.