Circular Ring 2Circular Ring 2 in Obsidian BlackCircular Ring 2 in Obsidian BlackCircular Ring 2 in Obsidian BlackCircular Ring 2 in Obsidian BlackCircular Ring 2 in Obsidian BlackCircular Ring 2 in Obsidian BlackCircular Ring 2 in Obsidian BlackCircular Ring 2 in Obsidian Black

Circular Ring 2

The smart ring for 24/7 health tracking

$299.00 $349.00 Sale 14%

4.5 191 reviews

140+ biosignals across 13+ health features, from a single-lead ECG to AI coaching. A health lab on your finger, with no mandatory subscription.

Clinical-grade ECG and AFib detection — forty seconds at your finger, result in the app.
Free feature upgrade — Blood Pressure, glucose trends and more coming soon.
Kira AI health coach — your own numbers, read back in plain language.
No mandatory subscription — every core feature included with the ring.
ColorObsidian Black
Größe
Add to your order

As covered inForbesWiredTechCrunchVogue
Worldwide shipping 14-day returns 1-year warranty 24/7 support
No mandatory subscription

Every core feature is included with the ring — ECG, sleep, recovery, stress, cycle tracking, vital alerts. Competitors charge monthly for less.

HSA / FSA HSA/FSA eligible in the US

Pay with pre-tax dollars and keep roughly $90 of this order. We send the documentation for your records.

How it works

Pay with pre-tax dollars from a Health Savings or Flexible Spending Account. We send the documentation you need for your records.

Circular Ring 2 Circular Ring 2 6 / Obsidian Black $299.00$349.00 Worldwide shipping · 14-day returns

By the numbers

140+Biosignals tracked
13+Health features
8daysDays of battery
3gGrams of titanium
The Circular Ring 2 in silver titanium, seen head on
Worldwide shippingon any non-discounted order
14-day returnno questions asked
1-year warrantyextendable at checkout
24/7 supportreal people, same day

What it measures

Thirteen health tools, one ring.

Every core feature is included with the ring.

Latest ECG Sinus rhythm

62bpm

ECG and AFib detection

Forty seconds at your finger, screened for atrial fibrillation, exportable as a PDF.

Latest estimate Optimal

116/74 mmHg

Blood pressure

Pulse transit time between the ECG and PPG sensors, calibrated monthly to your own cuff.

Last night Restorative

86/100

Sleep

Four stages, breathing rate and blood oxygen through the night, scored by morning.

Energy today Steady

72%

Activity and energy

Energy across the day, not only the steps you counted.

Readiness Ready

78/100

Recovery

HRV and resting heart rate against your own baseline, not a population average.

Alerts this month All clear

2reviewed

Wichtige Alarme

Free on every ring. Speaks up when something moves away from your normal.

Balance today Calm

64/100

Stress

Where the load fell today, and whether to train or rest tomorrow.

Cycle day Ovulation window

14of 29

Women's health

Cycle, fertile window and hormonal phase, read from nightly temperature.

Circular age 3 below actual

31years

Longevity

A biological age you can actually move.

Woke at Light sleep

6:42am

Wake Up

A vibration at your lightest moment inside the window you set.

Taken on time On track

94%

Medication reminder

A tap on the finger, logged whether or not the phone is near.

Live heart rate Measuring

68bpm

Live measurements

Heart rate, oxygen and temperature on demand, in ten seconds.

Session Coherence 6/min

4:00min

Geführte Atmung

Paced breathing at six a minute, with HRV as the read-out.

See it work

Forty seconds, and a rhythm you can read.

Single-lead ECG · press to record 0:00

Two months in

What our users experienced over 2 months.

86%Slept better
92%More energy
79%Sharper focus

The differentiator

A clinical reading, on demand.

The arteries are closer here than a wrist can reach.

Why the finger

The arteries are closer here than a wrist can reach.

Which is why a ring can take a single-lead ECG in forty seconds, hold a clean signal through the night, and estimate blood-pressure trends a watch cannot. Everything Circular does follows from where it sits.

Thirty seconds at your finger, screened for atrial fibrillation, exported as a PDF your cardiologist can actually read.

Advanced health features

Every signal your body gives, translated.

Tracked, analysed and turned into guidance you can act on.

ECG + AFib detection

Track your heart rhythm with medical-grade technology and catch signs of arrhythmia before symptoms appear.

Kira coaching

Ihr KI-Gesundheitscoach übersetzt komplexe Daten in leicht verständliche, auf Ihren Lebensstil abgestimmte Tipps.

Schlafüberwachung

Monitor sleep stages, breathing and oxygen levels to understand how well your body recovers overnight.

Ring versus wrist

Smaller, lighter, and still on at 3am.

Circular Ring Wrist tracker
Weight 3 g 45 g
Thickness 2.55 mm 11 mm
Battery 8 days 18 hours
Worn to sleep Every night Charging
Screen to check None Always

Wrist figures are typical for a mainstream smartwatch.

Drawn, machined, then worn by the people who built it.

How it is made

Drawn, machined, then worn by the people who built it.

Titanium body with a PVD finish, hypoallergenic inside, 2.55 mm thick. Every algorithm is validated against clinical reference hardware, and every engineer on the team wears the ring — which is how the bugs get found before you do.

2.55mmThickness
7.8mmWidth
3gWeight
IP68Water rating
No screen. No buzzing. Eight days between charges.

Entwickelt, um nicht abzulenken

No screen. No buzzing. Eight days between charges.

Four grams of titanium with a PVD finish, 2.55 mm thick, hypoallergenic inside. Waterproof enough for the shower, the pool and the rain — worn through sleep without you noticing it.

Battery

Eight days on, thirty minutes off.

8days of wear 30minutes to full

Power mode. Around five days in performance mode, with high-frequency measurement.

Kira

Data is not the product. Understanding is.

You wear the ring. Kira does the reading.

The app

You wear the ring. Kira does the reading.

The ring captures the signals; the app turns them into plain sentences. Kira watches for changes in your vitals, flags early warning signs, and tells you what to do about today — no dashboard to decode.

Silver, obsidian, gold, rose gold.

Four finishes

Silver, obsidian, gold, rose gold.

The same ring underneath. Pick the one you would wear without thinking about it — the sensors, the battery and the features are identical across all four.

In the box

What arrives.

Circular Ring 2

Titanium, four finishes, nine sizes.

Wireless charging case

Protects, powers and travels with it.

USB-C-Kabel

For the case. Thirty minutes to full.

Cleaning cloth

Keeps the sensors and the finish clear.

App access

iOS and Android, with the digital user guide.

Specification

Four grams of titanium.

BodyTitanium, hypoallergenic interior
Size2.55 mm thick, 7.8 mm wide, 3 g
SizesUS 6-14
Battery8 days power mode, 5 days performance
Charging30 minutes, wireless case
SensorsECG, PPG, temperature, 3-axis accelerometer
ConnectivityBluetooth Low Energy, airplane mode
CompatibilityiOS and Android
ComplianceGDPR and HIPAA

Trusted by people who live well.

Who wears it

On the grid, on the court, in the clinic.

Drivers, athletes and clinicians wear the same ring you do — the same sensors, the same app, no professional edition.

Romain Grosjean
Romain Grosjean

Formula 1 and IndyCar driver

Clint Capela
Clint Capela

NBA player

Dr Boon P Lim
Dr Boon P Lim

Consultant cardiologist and electrophysiologist

Questions

The ones that matter.

No. Every core feature is included with the ring: ECG, four-stage sleep, energy, smart alarm, vital alerts, guided breathing, stress, chronotype, cycle tracking, activity, HRV, temperature, blood oxygen and live measurement. A small number of advanced screens are premium, and can be unlocked with coins you earn by wearing the ring rather than with money.

Choose the sizing kit. We post a set of replica rings in every size — wear the one that fits for a day, tell us which it was, and your ring ships. Nothing more to pay. If you already know your size, pick it and we ship straight away.

Sensors and algorithms are validated against clinical reference equipment, and readings update roughly every two minutes. Blood pressure is a wellness trend rather than a diagnosis, and asks for a monthly calibration against an ordinary cuff.

Yes. Showers, swimming and daily wear are all fine.

Around eight days in power mode and four to five in performance mode, from a thirty-minute wireless charge.

Encrypted from ring to app to cloud, on servers that meet GDPR requirements, deletable by you at any time. We never sell or share health data.

Owners

What people say.

Prevention beats treatment. That is the whole reason this exists.

Mieux vaut prévenir que guérir — Circular, Paris
Circular Ring 2 · designed in Paris