Circular Ring 2 Titanium Smart Ring with ECG and No Required Subscription
A 2.55 mm titanium ring with ECG, PPG and temperature sensors, $349 to $549 by finish on Circular's US store on 2026-09-30.
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QUICK VERDICT
Circular Ring 2 is a titanium smart ring with an ECG sensor, bought once with no required subscription. Circular's US store prices it by finish, from $349 in Obsidian Black to $549 in Rose Gold or Gold, and the brand's own pages disagree on its battery life, charge time and return terms.
- Best for
- Buyers who want a titanium ring with an ECG sensor, paid for once with no required subscription, in a choice of four finishes from $349, and who are willing to order the $5 sizing kit and wait for it before the ring ships.
- Skip if
- You lift weights or carry heavy loads with a ring on; you want to wear it in a sauna or in the sea; you expect contactless payments, which the Ring 2 specification does not list; you need one settled battery or charge time figure before buying; or you would rather wait for Ring 3 pre-orders in December 2026.
- Tier
- Premium
Circular Ring 2 comes from Circular Health Limited, a Paris company that says it designs in France and mass manufactures in China. It is the one ring on Circular's US store, in four finishes at three prices, and the product page says the sensors, battery and features match across all four. Circular's terms of use state that the ring is not a medical device.
Four sensor types appear on the product page: ECG, PPG, temperature and a 3-axis accelerometer. The user guide names a single lead ECG sensor, a three LED oximeter sensor using infrared, red and green light, a digital temperature sensor and the accelerometer, while the home page counts seven sensors. Blood pressure estimates, which Circular calls a wellness estimate, need three readings from an ordinary cuff at setup and one every thirty days after that. Circular's pages describe that feature as included, as in testing and as live.
The app runs on iOS 15 and later and Android 9 and later. The product page says core features come with the ring and a few advanced screens open with coins earned by wearing it. A help centre article dated 2026-09-02 lists sleep, ECG recordings, HRV, SpO2 and cycle tracking as free, places blood pressure advanced insights, long term trends and PDF export of history in a premium tier paid with coins or by card in the app, and describes a Circular+ status subscription.
Circular's battery and charging numbers do not agree from page to page. In power mode they run from up to 6/7 days in the help centre to 8 days on the product page, and the stated charge time ranges from 30 minutes to about ninety minutes depending on the page. The charging case carries its own battery and fits one ring size only.
Circular rates the ring IP68, but its user guide and help centre advise against salt water and sauna wear, and the user guide advises against wearing it for weight lifting or carrying heavy items.
Sizes run US 6 to 14 with no half sizes, and Circular's sizing page and help centre disagree on whether they follow the standard US scale. The sizing kit option costs $5 more and ships before the ring. The warranty runs one year from delivery.
Circular says Ring 3 pre-orders open in December 2026, with an unpublished upgrade price for Ring 2 owners.
Buyers who want a titanium ring with an ECG sensor, paid for once with no required subscription, in a choice of four finishes from $349, and who are willing to order the $5 sizing kit and wait for it before the ring ships.
You lift weights or carry heavy loads with a ring on; you want to wear it in a sauna or in the sea; you expect contactless payments, which the Ring 2 specification does not list; you need one settled battery or charge time figure before buying; or you would rather wait for Ring 3 pre-orders in December 2026.
Specifications
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Where this fits
Circular Ring 2 (model CR2) cross-shops across several editorial surfaces on this site: the full brand catalog, the price band it qualifies for and the in-depth guides for its category.
Circular Ring 2 (model CR2) - buyer FAQ
How much does the Circular Ring 2 cost?
On Circular's US store on September 30, 2026, the ring was $349 in Obsidian Black, $449 in Silver and $549 in Rose Gold or Gold, the same in every size. The sizing kit option adds $5. A store banner advertised up to 30% off applied at checkout, which we did not open. Circular's /shop page lists the ring at $299, while its home page gives $349.
How long does the Circular Ring 2 battery last between charges?
Circular publishes several figures. The product page gives 8 days in power mode and 5 in performance mode, and its FAQ says four to five for performance. The user guide says up to 7 days in power mode, and a help centre article says up to 6/7 days, or 3/4 days in performance mode depending on ring size.
Can I swim or use a sauna with the Circular Ring 2 on?
Circular rates the ring IP68. Its user guide allows immersion to 50 meters for a maximum of 30 minutes and advises against salt water, while its home page lists open water swimming among the uses and rules out diving. For heat, a help centre article advises against sauna wear and gives a maximum working temperature of 60°C (140°F).
Should I buy the Circular Ring 2 or wait for the Ring 3?
Circular says Ring 3 pre-orders open in December 2026 and that Ring 2 keeps receiving the new software features. It also says Ring 2 owners get a special upgrade price for the first three months after pre-orders open, and it does not publish the amount. Circular's Ring 3 page advertises Ring 2 at up to 30% off in the run-up to that launch.
Circular Ring 2 Titanium Smart Ring with ECG and No Required Subscription
$349 to $549 · Verified 2026-09-30
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