01WORKDAY STRESS
Understand stress.
Find time to reset.
Recognize demanding moments. See when a breathing break may help.
Daytime StressTODAY
A demanding day.
A moment to reset.
Elevated
9 AM12 PM3 PM
Your day in moments
CIRCUL RING
CIRCUL RING 3
Shipping calculated at checkout.
Total
Free Shipping
1 Year Warranty
30 Days Returns
Secure Checkout
Taxes and duties may apply depending on your shipping destination.
PRODUCT FEATURES
- Adaptive-Fit Design for 24/7 Comfort: Reengineered for CIRCUL 3, the new two-segment design adapts to natural changes in finger size within the adjustment range of your selected size, helping maintain a comfortable, secure fit throughout the day.
- Ultra-Thin Titanium Design: At approximately 2.23 mm, CIRCUL 3 is our thinnest ring yet. A refined titanium design combines continuous sensing and Adaptive Fit in a lighter everyday form.
- Sleep Tracking & Nighttime Breathing: Tracks sleep stages, Sleep Debt, overnight blood oxygen trends, respiratory rate and nighttime breathing patterns to give you a clearer picture of your sleep and overnight recovery.
- Heart Rate, HRV & Health Trends: Tracks heart rate, resting heart rate, HRV, RMSSD, SDNN, heart rhythm, temperature trends and BP health trends, with long-term trends to help you understand changes over time.
- Daily Recovery & Body Resilience: See Daily Recovery, Stress Radar, Resilience and long-term HRV trends together, helping you understand when your body is ready to push and when it may need more recovery.
- Real-Time HRV Biofeedback & Guided Breathing: Follow a guided five-minute breathing session while CIRCUL tracks HRV-related signals, then review your physiological response when the session ends.
- Women’s Health & Cycle Insights: Connect menstrual cycle patterns with temperature, HRV, heart rate and sleep to better understand how different signals change together throughout your cycle.
- Automatic Activity Tracking: Automatically recognizes daily activities, tracks workouts and monitors exercise heart rate, with less manual logging.
- Up to 7 Days. No Monthly Subscription: Get up to 7 days of ring battery life* under supported conditions. Included CIRCUL health and wellness insights require no monthly subscription.
SPECIFICATIONS
- Material
- Titanium
- Profile
- Approx. 2.23 mm*
- Width
- 6.8 mm*
- Weight
- Approx. 2.5–3.5 g*
- Fit
- Dual-Segment Adaptive Fit
- Starting sizes
- XS / S / M / L / XL / XXL
- Total coverage
- Approx. US 5–14.5*
- Optical sensing
- Tri-wavelength PPG — Green / Red / Infrared
- PPG sampling
- Up to 100 Hz during sleep*
- Sensors
- PPG / Temperature / Accelerometer
- Water resistance
- 10 ATM*
- Battery
- Up to 7 days*
- Charging
- Charging dock included
- Compatibility
- iOS / Android
- Connectivity
- Bluetooth
- Subscription
- None required
*Dimensions, weight and fit coverage vary by ring size. Battery life depends on ring size, settings and use. PPG sampling rates vary by operating mode. Water resistance depends on use conditions.
Product information
# 30-Day Return Policy
You may request a return within 30 days from the date of receiving your Circul smart ring. Please NOTE that, return shipping costs are generally borne by the user.
Friendly Reminder:
If you encounter any functional issues or have questions while using your product, we kindly encourage you to contact our support team first.
Friendly Reminder:
If you encounter any functional issues or have questions while using your product, we kindly encourage you to contact our support team first.
Before submitting a return or refund request, we encourage you to review the CIRCUL RING 2 MAX Usage & Care Guide (click here: https://circulsense.com/pages/circul-ring-2-max-usage-care-guide). The guide includes proper wearing instructions, charging precautions, daily maintenance recommendations, and troubleshooting tips. Some issues may be resolved through correct usage and care.
We will review each case individually and, while adhering to the existing refund policy, provide you with helpful and personalized assistance.
1. Full and Partial Refund Conditions
If any of the following conditions are met, a refund will be provided (minus actual shipping costs):
• Scenario One: Full Refund
- Unopened product: Product packaging and seals remain in their original condition, with no unpacking;
- Opened but meets new standards: Although the product has been unpacked and used, there are no signs of use or damage, all accessories (charging case, manual, etc.) and gifts are complete with no missing items, packaging has only minor opening that does not affect resale, and no functional abnormalities caused by human operation.
• Scenario Two: Partial Refund
If the product has been used and meets the following conditions, a partial refund may be requested:
- Product functions normally with only minor signs of use that do not affect resale;
- Original accessories, packaging, and gifts are mostly complete;
- No obvious bumps, paint loss, scratches, or other appearance damage.
Refund percentages are as follows:
- Light use (product intact, no scratches, fully functional) : 80%-90% refund;
- Minor wear on appearance: 60%-80% refund.
2. Non-Refundable Situations
Refunds will not be provided in the following cases:
- Severe exterior wear: Product has obvious scratches, bumps, paint loss, or other issues affecting resale;
- Functional abnormalities: Malfunctions caused by human factors such as dropping, water damage, or improper use;
- Missing or damaged accessories: Original accessories or gifts are lost/damaged, affecting complete return;
- Unofficial modifications: Self-disassembly, modification, or problems caused by using non-official accessories;
- Significant signs of use: Product shows obvious long-term use resulting in performance decline or natural wear;
- Customized/discounted items: Products clearly marked as "non-returnable" on their product page, including customized items or promotional products;
- Beyond return period: Return request submitted more than 30 days after receipt.
3. Return Process
- To return, you may submit an application through your Order or contact Customer Support to obtain the return address and operation guidelines;
- When returning the product, please choose trackable, insured shipping and keep the tracking number for verification.
4. Refund Processing
- Orders that qualify for full or partial refunds will be processed within 5 business days;
- We will deduct reconditioning fees and shipping costs according to the refund percentage, and return the balance through the original payment method;
- For orders paid with coupons or gift cards, refunds will be calculated based on the actual payment proportion.
5. Special Notes
- Return shipping costs are generally borne by the user;
- if there are product quality issues, users may apply for shipping cost reimbursement with valid proof after verification;
- Circul reserves the right to adjust the content of this policy based on actual circumstances and will notify users of updates through official channels.
# Exchange
If the item you received is unused and in its original condition, and you would like to exchange it for a different size or color, you have two options:
-
Exchange (Recommended):
Please contact our customer service team directly. If the item meets our return and exchange criteria, we will assist you in exchanging it for the desired size or color.Please note that you will be responsible for the shipping cost of the exchange. -
Return and Reorder:
You may also choose to submit a return request and place a new order for the desired item.
In this case, unless the item has a quality issue or was damaged during shipping, any previously paid shipping fees, handling charges, or taxes will not be refunded.
Important Notes:
-
Please contact our customer service team first to confirm your eligibility and obtain the correct return address before sending any item back. Do not return any product without authorization—unauthorized returns will not be processed, and any resulting risks or costs will be your responsibility.
-
Exchange requests are subject to product availability. To ensure that the item you want is still in stock, we recommend reaching out to us as soon as possible.
# Refund
A full refund means you will receive the total amount of your order back if you return the product according to our return policy.
You may be eligible for a partial refund if:
-
We find any damages, contamination, wear and tear, or missing parts upon inspecting the returned product. We may deduct the devaluation amount from your refund unless these issues were declared in your return request.
-
You received bundled products or gifts. To receive a full refund, we recommend returning all bundled items. If you cannot return them, we may deduct the corresponding amount from your refund.
Please note: You will be responsible for all costs associated with returning the product unless the return is due to defects, damages, or non-compliance, and you have provided supporting photos and descriptions.
Processing Time for Returns or Exchanges
For return requests that comply with our policy, we will initiate the refund immediately upon receiving the returned product. The refund will be processed through the original payment method and may take up to 10 calendar days.
#Warranty Coverage for CIRCUL RING
All original components of new products are covered by a 1-year warranty in non-European Economic Area (EEA) countries and a two-year warranty in EEA countries. Claims must be made directly to CIRCUL with proof of purchase. The warranty applies to the original owner and is transferable to subsequent owners. If damage is due to craftsmanship defects, CIRCUL will repair, replace, or refund.
Exclusions from Warranty Coverage
The warranty does not cover:
-
Improper or negligent use, operation, or modification.
-
Maintenance contrary to product care instructions.
-
Normal wear and tear.
-
Rechargeable batteries, which have limited lifespans and are considered consumable items. Battery replacement is not included in the standard warranty.
-
Damage or defects caused by accidents.
# Circul Ring Extended Warranty Terms
1. Service Overview:
After purchasing this extended warranty service, the basic warranty period of your smart ring will be extended, with the specific duration determined by the service type you select. During the extended warranty period, you can enjoy free product replacement service at the same standard as the original warranty period.
2. Coverage:
Free replacement with a brand new product is available for manufacturing defects (including sensor malfunction, significant battery life deterioration, material and workmanship defects, etc.) and functional failures that occur during normal use. However, issues that can be resolved through firmware upgrades via the APP are not covered by this extended warranty service.
3. Exclusions:
Human-caused damage resulting from drops, water immersion, crushing, etc. due to failure to follow official operating instructions; malfunctions caused by unauthorized disassembly, modification, or use of non-official accessories; appearance wear and normal aging of consumable parts (such as charging cables) are all excluded from the extended warranty coverage.
4. Service Process:
If your product experiences issues during the extended warranty period, you may apply for after-sales service through the official APP or Customer Support. Follow the instructions to return the product, and after verification that it meets the conditions, a brand new replacement product will be shipped to you within 10 business days.
5. Additional Notes:
This extended warranty service is non-transferable and applies only to the originally purchased smart ring; no refunds are supported after the service becomes effective; the company reserves the right of final interpretation and modification of the extended warranty terms, and users will be notified of any modifications through official channels.
Overview
Real-Time Tracking
Data updates every second.
AI-Powered Sleep Tracking
Understand your sleep stages and overnight patterns.
HRV Biofeedback
Follow guided breathing exercises and see your body's real-time response.
Breathe.Follow the rhythm.
LIVE HRV54ms
Cuff-Free Blood Pressure
Get blood pressure readings, no bulky arm cuff required.
Personal baseline
Ultra-Thin
Adaptive Smart Ring.
A More Flexible Fit. All-Day Comfort.
2.23mmAerospace-grade titanium
BIDIRECTIONAL ADAPTIVE FIT
Long-Term Health Insights
Understand your health patterns over time.
Extended Battery Life
More time wearing. Less time charging.
Up to7days*
Water Resistance
10 ATM protection for everyday wear.
Advanced Optical Sensing
Powered by SST™ Ultra 3.0 sensing technology.
No Monthly Subscription
Your data. No recurring charges.
Cycle Tracking
Track cycle changes through temperature, HRV and sleep trends.
Across your cycle.
NEXT-GENERATION SMART RING FIT
The World’s Thinnest Adaptive Smart Ring
Adapts to your finger's natural changes, keeping sensors close to your skin.
CIRCUL 3 · MADE TO ADAPT01 / 05
Illustrative lifestyle scene
DAILY FIT
Self-Adjusting Fit
Expands and contracts as your finger changes.
Fit, finger choice & gifting
Adaptive Fit accommodates everyday changes within the selected ring size’s range. You can switch between supported fingers when each falls within that range and the ring maintains comfortable, consistent sensor contact.
For a gift, use the recipient’s measurements to choose a starting size. Longer-term body changes, including weight change, may mean checking the fit again.
*Fit varies by finger and starting size. Lifestyle images and the layer view are illustrative and do not represent actual size measurements.
RECOVERY & RESILIENCE
Breathing Coach& Everyday Recovery
Breathe with guidance. Understand stress. Build resilience.
Understand stress.
02ACTIVE BREATHING
Guided breathing.
A moment to reset.
Follow a gentle rhythm: four seconds in, six seconds out.
Breathing CoachGET READY
Make room for a reset.
5:00Find a comfortable seat.Let the pace guide you.
Breathe in4s
GUIDED BREATHING PACE
6breaths/min
Inhale 4s · Exhale 6sSESSION COMPLETE
See How Your Body Responds.
Starting HRV42ms
Ending HRV54ms
A clearer view of your body's response to guided breathing.
Session preview · Example data
03LONG-TERM RECOVERY
Track recovery.
Build better habits.
See how your body responds to stress. Track resilience trends over time.
Body Resilience4-WEEK VIEW
Excellent
Compared with your baselineAdaptation, over time.
CurrentPersonal baseline
HRV (SDNN)88 msRespiratory rate14 brpmResting heart rate55 bpm
Example from CIRCUL InsightExplore insights
Stress is elevated. Make room for a breathing break.
Follow a five-minute session. Let the rhythm guide you.
See how stress and recovery are changing over time.
01 / 03Scroll to explore
Illustrative experiences and data. Individual responses vary.
SLEEP INTELLIGENCE BY CIRCUL AI
AI-Powered Sleep Tracking& Nighttime Breathing
From every second of sleep data to insights that matter.
TO MORNING.
CIRCUL 3 · YOUR NIGHT, CONNECTED
01 / EVERY SECOND
Every second counts.
Oxygen trendsBreathing patterns
1sec
Blood oxygen sampling.
Throughout the night.
Blood oxygen statistics
02:17 AMAverageEstimated events
1-sec samples · replayOVERNIGHT ODI
28.4oxygen dips / hr
Moderate
051530
See every second in the CIRCUL app. Export your report as a PDF.
02 / THE ESSENTIALS, TOGETHER
Your night at a glance.
7h 42mTotal sleep
Sleep debt: 0m
23:0007:00
AwakeREMLightDeep
- Sleep score
- 89Good
- Sleep recovery
- 78
- Avg. blood oxygen
- 90%↓ 5%
- Heart rate
- 55bpm
- HRV · SDNN
- 88.3ms
- Skin temp
- +0.1°C
AI MONTHLY REPORT · OCT 2026
Your month. Made clear.
Sleep score
83
Latest
+13 since 10.01
MONTH TO DATE ·OCT 1–17, 2026.
CIRCUL AI · Monthly insights
Summary
Your weekly average rose from 73 to 79, comparing Oct 1–7 with Oct 11–17, 2026.
Possible factor
Later bedtimes may be shortening sleep on lower-score nights.
Try this week
Keep a steady wake-up time and start winding down 30 minutes before bed.
Illustrative data and AI insights.
EVERYDAY HEALTH
30+ Health Metrics & Insights
Sleep. Recovery. Heart health. Activity. Your cycle.
Sleep Stages
See your awake, light, deep, and REM sleep stages to understand the rhythm of your night and spot subtle changes that may affect sleep quality.
Sleeping Heart Rate
Track your heart rate throughout the night to understand how your body settles into rest and recovers.
Sleep HRV (RMSSD)
Explore subtle changes in the time between heartbeats to understand how relaxed your body is during sleep and how your recovery trends over time.
Sleep HRV (SDNN)
Track overall heart rate variability throughout the night to understand trends in how your body regulates itself.
Sleep Breathing
Follow your overnight breathing rate and rhythm to see how steadily you breathe while you sleep.
Blood Oxygen (SpO₂)
Track your overnight blood oxygen levels and patterns to see how they change while you sleep.
Sleep Movement
Track tossing, turning, and body movement throughout the night to understand nighttime activity and potential sleep disruptions.
Sleep Score
Bring key sleep metrics together in one easy-to-read score for a quick look at how well you slept.
Recovery Score
Wake up with a clearer sense of how ready your body is for the day ahead.
Sleep Debt
See your accumulated sleep shortfall and understand how much more rest you may need.
Sleep Skin Temperature
Follow your overnight skin temperature with its average, highest and lowest readings.
Stress Radar
See how stress changes throughout your day, with a clearer view of your body’s signals.
Guided Breathing
Follow a structured breathing rhythm to relax your body and mind and gradually ease tension.
Breathing Rhythm
HRV analysis automatically identifies your personalized breathing rhythm, designed to help you relax and ease stress.
Breathing Session Insights
Compare heart rate and other signals before and after each breathing session to understand your body’s relaxation response.
Daily Activity
See how close you are to today’s activity goal and how much more movement you need to reach it.
Daily Steps
Track every step and keep your daily activity goal in sight.
Activity Intensity
Track time spent at different activity levels to see how much you move each day and how you’re progressing toward your activity goals.
Recorded Session
Review each workout’s duration, steps, calories and average heart rate.
Activity Tracking
Track your workout heart rate, steps, and intensity, with a clear record of every session.
Blood Pressure
Compare calibrated blood pressure estimates with your usual readings.
Daily Heart
Follow your heart rate throughout the day to understand how your body responds during activity, rest, and sleep.
Resting Heart Rate
Follow changes in your resting heart rate to understand your body’s rest and recovery trends.
Heartbeat Rhythm Map
See how the time between one heartbeat and the next relates to the following interval, revealing patterns in your heartbeat rhythm.
Heartbeat Interval
Explore changes in the time between heartbeats and how those intervals are distributed for a clearer picture of your heartbeat rhythm.
Heart Status
Bring heart rate and rhythm patterns together in an easy-to-read status level, helping you understand changes in your body and keep track of your heart health.
Body Resilience
Follow how your body adapts to stress and recovers over time, with a clearer view of your long-term health trends.
HRV (SDNN)
Track changes in your HRV against your personal baseline built over multiple days to understand your body’s overall regulation and long-term health trends.
HRV (RMSSD)
Compare RMSSD with your personal baseline built over multiple days to follow long-term relaxation and recovery trends and spot changes worth a closer look.
Average Sleep Breathing Rate
Compare your average breathing rate each night with your personal baseline built over multiple days to understand breathing stability and spot longer-term changes worth noting.
Average Sleep Resting Heart Rate
Compare your average resting heart rate each night with your personal baseline built over multiple days to follow overnight recovery trends and spot changes worth noting.
Sleep Heart Rate Trend
Follow second-by-second heart rate changes throughout the night alongside longer-term trends to understand your overnight recovery patterns and spot changes worth a closer look.
Sleep Breathing Rate Trend
Follow second-by-second breathing rate changes throughout the night alongside longer-term trends to understand your breathing rhythm and stability and spot changes worth noting.
Period Tracking
Record period days to follow your cycle over time.
Period Forecast
Plan ahead with an estimate of when your next period may start.
Cycle Temperature
Follow skin temperature changes alongside your cycle.
More Coming Soon
More women’s health insights are on the way.
App examples from different records. Charts are simplified illustrations. Individual patterns vary.
Sleep Apnea Risk Assessment provides risk-related context and is not intended to diagnose sleep apnea.
CIRCUL APP
Your Health, All in One Place.
Sleep, recovery and everyday health. Connected in one app.
01 / 02
Daily overview
Recovery, sleep and activity, with your daily health snapshot.
App screen previews · Sample data from different dates.
Sun, Oct 18
OptimalResilience is optimal. SDNN is below baseline; RMSSD is near usual.
Sleeping heart rate is low, with steady breathing.
GoodGood sleep quality. Sleep was shorter and later than usual, but efficient.
Sleep stages were balanced, with little overnight movement.Stable
StableRecovery is stable, with lower sleeping heart rate and strong HRV.
Shorter sleep limited overall recovery.Good
GoodAverage and lowest HR were slightly below usual; maximum was typical.
HRV stayed strong. Brief increases did not change the overall good pattern.Balanced
BalancedTemperature stayed in your usual range, with only small, brief changes.
2.23 MM TITANIUM SMART RING
Ultra-Thin Titanium. Liquid Light Finish
Jewelry-inspired titanium. Made for everyday wear.
CIRCUL 3 / DESIGN STUDY
Drag to rotate the ring
LESS, IN EVERY DIMENSION
2.23mm*
2.23 mm Ultra-Thin Design
A slimmer profile. A lighter feel for everyday wear.
6.8 mm*Refined width
2.5–3.5 g*Light on your hand
A Smart Ring You’ll Want to Wear Every Day.
Slim titanium. A smooth inner surface. Designed for comfort from work to sleep.
Liquid Light Finish.
Subtle reflections. A refined feel.
Advanced Sensing. Deeper Insights.
Heart, temperature, and motion sensors work together to reveal deeper insights into your sleep, recovery, and daily activity.
Compare
Smart Rings
The details that make a daily difference.
Swipe to compare
| Category | Feature | CIRCUL 3 | Oura Ring 5 | RingConn Gen 3 | Ultrahuman Ring PRO |
|---|---|---|---|---|---|
| Design & fit | Design & fitAdaptive fit | Adapts as your finger changesHidden Six-Spring Mechanism with Controlled Motion |
Not supported. Fixed size |
Not supported. Fixed size |
Not supported. Fixed size |
| Wearing comfort | Adaptive Fit— Comfortable, Secure & Pressure-Relieving |
Fixed Fit— May Feel Too Tight or Too Loose |
Fixed Fit— May Feel Too Tight or Too Loose |
Fixed Fit— May Feel Too Tight or Too Loose |
|
| Primary Inner Surface Material | Titanium Alloy |
Titanium Alloy |
Epoxy Resin |
Titanium & Hypoallergenic Plastic |
|
| Dimensions | DimensionsThickness | 2.23 mm |
2.28 mm |
2.3 mm(at thinnest point) |
2.65 mm |
| Width | 6.8 mm |
6.09 mm |
6.8 mm |
Approx. 8.2 mm |
|
| Sleep monitoring | Sleep monitoringSampling rate | High sample rate 100 Hz |
Not confirmed or disclosed for this feature. Not Disclosed |
Not confirmed or disclosed for this feature. Not Disclosed |
Not confirmed or disclosed for this feature. Not Disclosed |
| Heart rate resolution | 2-Second Intervals |
Supported. 5-Minute Resolution |
Supported. 2.5 Minutes |
Not confirmed or disclosed for this feature. Not Confirmed |
|
| Respiratory rate monitoring | Breath-by-Breath Tracking |
Supported. Nightly Average |
Supported. Nightly Average |
Not confirmed or disclosed for this feature. Not Confirmed |
|
| HRV | HRVHRV metrics | RMSSD · SDNN · Lorenz plot |
Supported. RMSSD |
Supported. RMSSD |
Supported. RMSSD |
| Stress, recovery & resilience | Stress, recovery & resilienceBreathing training | Supported with Biofeedback(Breathing rate, HR, HRV) |
Supported. Supported with Biofeedback(HR, HRV) |
Not supported. Not supported |
Supported. Supported |
| Stress & recovery | Stress Radar · Daily Recovery |
Supported. Daytime Stress · Readiness |
Supported. Stress & recovery insights |
Supported. Stress Rhythm |
|
| Resilience | Body Resilience— Personal Baseline & Long-Term Physiological Trends |
Supported. Stress Resilience— 14-Day Stress & Recovery Balance |
Not confirmed or disclosed for this feature. Not Confirmed |
Not confirmed or disclosed for this feature. Not Confirmed |
|
| AI | AIAI insights | CIRCUL AI |
Supported. Oura Advisor |
Supported. AI health companion |
Supported. Jade AI |
| Battery & pricing | Battery & pricingRing battery | Up to 7 days* |
6–9 daysVaries by size & use |
11–14 daysVibration off; 10–12 days on |
Up to 15 daysTurbo ~12; Chill 15+ |
| Price · USD | $239*Current launch plan |
From $399Finish-dependent pricing |
From $349 |
$479PRO Charging Case included |
|
| Subscription | $0 / monthNo monthly fee |
$5.99 / monthUS membership · $69.99 / year |
$0 / month |
$0 for core featuresOptional paid PowerPlugs |
CIRCUL 3 — Lighter. Stronger. Smarter. A Better Fit.
| Category | Feature | CIRCUL 3 | CIRCUL 2 MAX |
|---|---|---|---|
| Design & fit | Design & fitFit Technology | Next-Generation Adaptive Fit |
Adjustable Fit |
| Design | Hidden Six-Spring Mechanism with Controlled Motion |
Classic Four-Direction Expansion Mechanism |
|
| Material | Aerospace-Grade Titanium Alloy |
316L Stainless Steel |
|
| Weight | 2.5–3.5 g— Approximately 50% Lighter |
5.6–7.1 g |
|
| Width | 6.8 mm |
8.8 mm |
|
| Thickness | 2.23 mm |
2.6–3.3 mm |
|
| Wearing Comfort | Lightweight, Comfortable & Protrusion-Free |
Flexible Fit |
|
| Structural Strength | 3× the Structural Strength of CIRCUL 2 Max |
Previous-Generation Design |
|
| Health tracking | Health trackingHeart Rate Monitoring | Supported |
Supported |
| HRV Monitoring | Supported |
Supported |
|
| Blood Oxygen Monitoring | Supported |
Supported |
|
| Sleep Tracking | Supported |
Supported |
|
| Recovery & insights | Recovery & insightsBreathing Training | Supported |
Not Supported |
| Health Insights | Advanced Recovery & Body Resilience Insights |
Essential Health Trends |
|
| Everyday use | Everyday useWater Resistance | 10 ATM Certified· Enhanced Sealing Design |
5 ATM |
| Battery Life | Up to 7 Days |
Up to 7 days*Continuous tracking mode |
|
| Membership | No monthly fees |
No subscription required |
CIRCUL 3 highlightAvailableNot supportedNot confirmed
Comparison notes & sources
An x beside “Not Disclosed”, “Not confirmed”, “Not specified” or “To be confirmed” means this feature or specification has not been disclosed or verified. It does not mean the product lacks the feature. CIRCUL 3’s purple icons highlight its features; they do not claim every feature is exclusive.
* Sampling rate applies during sleep and is not the app refresh rate. Tracking depends on the enabled mode and supported conditions. Dimensions and battery life vary by size, settings and use. RingConn lists 10–12 days with vibration on; Ultrahuman battery life varies by mode.
Risk assessments and BP-related trends provide wellness context, not medical diagnoses or direct blood pressure readings.
Prices are in USD and vary by finish and configuration. CIRCUL 3’s $239 price reflects the current launch plan. Ultrahuman offers optional paid services.
Battery life varies by ring size, settings and use. CIRCUL 2 MAX battery life is stated for continuous tracking mode.
WHAT THIS MEANS
THE DETAILS
CIRCUL 3 Tech Specs
The essentials, down to the details.
Design & fit
- Material
- Titanium
- Surface
- Liquid Light finish*
- Fit
- Dual-Segment Adaptive Fit
- Fit coverage
- Approx. US 5–14.5*
Sensors
- Optical
- Green · Red · Infrared PPG
- Temperature
- Temperature sensor
- Motion
- Accelerometer
- Sampling
- Up to 100 Hz during sleep*
Battery & charging
- Ring battery
- Up to 7 days*
- Charging dock
- Included
App & connectivity
- Phones
- iOS & Android
- Connection
- Bluetooth
- Companion app
- CIRCUL App
- Membership
- $0 / month
What's in the box
CIRCUL 3 × 1
Magnetic Charging Base × 1
USB-C Charging Cable × 1
Quick Start Guide × 1
Still Got Questions?
Browse our FAQs to learn more.
What is CIRCUL 3?
CIRCUL 3 is CIRCUL’s latest adaptive smart ring, designed to help you understand your health patterns and practice recovery.
How does CIRCUL 3 compare to CIRCUL 2 MAX?
CIRCUL 3 brings a lighter, slimmer titanium-alloy design and next-generation adaptive fit for everyday comfort. It retains CIRCUL 2 MAX’s heart rate, HRV, blood oxygen and sleep tracking, while adding breathing training and advanced recovery and Body Resilience insights. Water resistance also increases from 5 ATM to 10 ATM.
What is HRV Biofeedback breathing?
It combines guided breathing with feedback on your body’s response, so you can observe how your physiology changes during a session.
What does Body Resilience mean?
It describes longer-term patterns in how your body adapts to challenges, recovers, and maintains balance. It is a wellness trend, not a medical assessment.
What does Circul AI do?
Circul AI is designed to turn your health data and personal patterns into insights that are relevant to you. It supports understanding your wellness trends; it is not a medical diagnostic tool.
Does Circul 3 provide medical diagnosis?
No. Circul 3 is for general wellness and is not intended to diagnose, treat, cure, or prevent any disease.
Does Circul 3 require a subscription?
No. Circul 3 does not require a recurring subscription.
How long does the battery last?
Battery life is up to 7 days. Actual battery life varies by ring size and model.
How water-resistant is Circul 3?
Circul 3 is rated 10 ATM.
This product has no reviews of its own. The merchant grouped it with related products, so the reviews shown are from across that group.
M
La bague Circul ring 2 max est super le système d’ajustement pour le doigt est très bien car jusqu’à présent j’avais la ring de chez oura mais difficile de trouver la bonne taille pour mon doigt et en plus pas d’abonnement.
D
I received my Circul Max 2 approximately 1.5 months ago and am in love with it. The app is so easy and gives you tons of information. I look forward to every morning, taking my blood pressure and reviewing my nights sleep. The adjustment is perfect. I am very active for 74 and between arthritic knuckles and swelling and shrinking, the ring is a perfect fit every time. I highly recommend!!
A
Initially I wasn't sure if I would like to wear a smart ring on my pointer finger but, given how it adjusts in size, I've found it to be comfortable. I've had my Circul Ring 2 Max for a few months now and no longer notice I'm wearing it. I also find the data it collects to be in-depth. I haven't learned what all the acronyms, etc. mean but I find the information collected about my health helpful. My only suggestion to share would be more specific tips. I seem to see the same tips each day so feel like they may be generic.
K
I appreciate that the Circul team pays close attention to their users' suggestions. This new model largely addresses the shortcomings of the original Circul Ring 2. It is definitely worth considering for purchase right now.
V
Love it! I can adjust it as I wish without worrying about moving it to another finger, can adjust it to whichever is best for me at the time, love the finishing details on the material and color, shipping could have be n faster but I cannot complain, will definitely buy another for my significant other.
G
Just got my ring last night and used the sleep apnea tracker and am impressed with all the data it provides. I am going to continue wearing it so that the ring adapts to my body and health to improve accuracy but am already happy with the data that I am getting! I do wish there was an option to switch the daily tracking intervals from every 10 minutes to 5min or lower. I would sacrifice battery life to be able to do that and do not mind having to charge it more often. I also wish there was a smart alarm option to wake you up at the best sleep stage. I can't wait for new updates and further improvements to come!
S
I've been wearing it for a couple of weeks and I must say that its functions have impressed me in a very positive way. The ring returns a lot of information on health and the results are of impressive precision. I had the opportunity to compare it with professional medical instruments and the ring returns a lot of information on health and the results are of impressive precision. Maximum rating more than deserved. But if I really have to be honest, the only real problem encountered is the support for the different languages. We are in 2025 and it is unthinkable that such a precise tool is important for our health supports only English or a little more and this in my opinion greatly limits the sale of the ring. But apart from this small negative note, the ring does 100% what it promises at a much lower price than the competitors.
A
I’m very impressed with the Circul ring. I have never left a product review before, this is how impressed I am! I have an autoimmune connective tissue disorder and sleep apnea, so accurate sleep and oxygen tracking was very important to me. Moreover, my fingers get puffy and swollen, and the Circul ring adapts to it. The oxygen measurements are the same as those of a medical-grade finger sensor! The app works seamlessly and the customer service is amazing. I think this is one of the best purchases I have ever made, considering the price and the accuracy of the product.
I’m happy with my purchase. The size fits all my fingers (a little loose on the pinky), and I’ve been using it daily with no issues—the tracking works well. Whether I’m washing my bike or doing the dishes, the ring continues to function and charge properly. I also like the flexibility of being able to swap it between fingers.
My only wish is that it could connect with other apps, such as Clue, similar to how the Oura ring does. Overall, it looks great on my fingers and I’m very satisfied.
K
This ring is everything I was looking for! The sizing was super easy, and it fits 8 of my 10 fingers. After the initial getting used to wearing a ring on my index finger {my finger of choice) it is quite comfortable. The continuous heart rate and SO2 monitoring is great, but my favorite thing by far is the sleep tracking. I was told I have sleep apnea many years ago, but ignored it. Eventhough I felt like garbage I never contributed it to sleep apnea. But the Circul ring has apnea monitoring that comes free with the ring and it made me admit that I had a problem. I started using my CPAP again and I feel great! I would have never done that had it not been for this ring.
The only negative I can think of is that the battery life, since I do use the apnea setting nightly. I have to charge it every day, but the charging case is so convenient that I can just toss the whole thing in a purse and put the ring back on when the green light flashes.
I would highly recommend this ring to absolutely everyone! I finally feel like I am taking control of my health, and this ring is definitely a key player!
L
I'm absolutely loving my Circul Ring. I got it in the space grey colour which i love. The size small fits my index, middle and ring fingers perfectly if I need to switch between fingers throughout the day. The adaptive fit is amazing and it's very comfortable. I have several health issues so I love that I can monitor my health around the clock. The blood oxygen, temperature, sleep apnea, etc are what are import to me with all of the other features. The real time monitoring is amazing! I'm looking forward to new updates etc and can't wait to see what you have in store for the near future. Thanks Circul Ring for making my health monitoring so much easier! Best money I've ever spent.
H
Awesome a ring that can take Bp readings !
G
Everything from sales to delivery was excellent
H
The adjustable design is incredibly useful, it fits four of my fingers, and on my index finger it’s so comfortable I can barely feel it’s there.
The sleep tracking is great! Even picking up on my naps. I was a bit worried about battery life before, but it really lasts 5–6 days with all-day wear, and the charging case is also convenient.
5 out of 5 stars. Looking forward to seeing more activity modes added!
S
I’m glad they replaced my defective Circul ring and made some great updates! I really like that it now monitors heart rate, oxygen saturation, stress, steps, sleep, HRV, skin temperature, and even sleep apnea. Such a cool and powerful device packed into a small ring!
C
It does what was advertised
A
I have to say the BP function matches my BP monitor almost exactly, it one the the features that seperates the Circul from the rest. Sleep monitoring is another great feature and wroks jsut as well. I get at least 5 days out of a charge.
C
This ring has been great with tracking my heart rate for Afib and sleep apnea. With that said, grabbing my dogs leash the other day caused the ring to shoot across the back yard. Otherwise this ring is amazing, for me.
P
I’ve had my CIRCUL 2 MAX for a little over 7 months now and I can’t say enough good things about it, it does take a little time to calibrate to your specific metrics. But I wear it on the same side as my 🍎and the numbers are within close proximity. The only logical reason for the difference is I have to charge the other device more frequently and I forget to put it back on!! Love love love my C2M, buying one for the wifey‼️
A
Amazing ring. Amazing data. Really informative, accurate. Works alongside my Garmin for my triathlon training. I can only give it 5 stars, but data, battery life, and flexible adjustable band works really well. Well done
