Device hub · Fitness rings · Desk research
Circular Ring 2
Ring 2 is the ECG-forward no-mandatory-sub ring: $299 sale / $349 list, 7.8 × 2.55 mm, 3 g, sizes 6–14, 50 m / 30 min in the guide.
Product images
Product photography stays on circular.xyz / shop.circular.xyz.
Credit: GadgetShowdown labeled placeholder (not a Circular asset). View official product image
Studio still only. Manufacturer press JPEGs are not hosted here. See the official product page for the real product photo.
In short
Ring 2 is the ECG-forward no-mandatory-sub ring: $299 sale / $349 list, 7.8 × 2.55 mm, 3 g, sizes 6–14, 50 m / 30 min in the guide. Buy it if you want on-demand ECG and will accept Circular’s wellness wording. Skip it if you need 100 m, a 10–14 day table, or a diagnostic ECG/BP device.
Who it is for
- Buyers who want a single-lead ECG on a ring and will treat it as wellness, not diagnosis.
- People who want core features without a mandatory membership (shop: ECG, sleep, recovery, stress, cycle, vital alerts included).
- iPhone or Android users (guide: App Store and Google Play).
- Shoppers who fit US sizes 6–14 and will use Circular’s replica sizing kit.
Who should skip it
- Anyone who needs 100 m water resistance. Guide: IP68, 50 m / 30 minutes; not recommended for long salt-water sessions.
- Buyers who want a 10–15 day OEM battery table.
- People seeking a diagnostic ECG, AFib device, or cuff-replacement BP meter. Guide: wellness only. Shop: BP is a wellness trend, monthly cuff calibration.
- Oura members who already like membership scores and 100 m titanium.
Key differentiators
- Single-lead ECG (~40 s) with PDF export; guide says wellness / not a medical device.
- No mandatory subscription for core features; shop says some advanced screens use earned coins rather than cash.
- Shop vs guide battery split is documented instead of averaged (8 vs 7 days; 30 vs 60 minute charge).
- 3 g titanium, 7.8 × 2.55 mm, sizes 6–14.
Caveats
- Do not average shop “8 days / 30 minutes” with the guide’s “up to 7 days / 60 minutes.” Cite both.
- ECG and blood-pressure rows stay in the manufacturer’s intended-use language.
- Charger is not waterproof; one charger size per ring size (guide).
- No hands-on testing. Shop social-proof percentages are not our lab.
Ring-category specs
Same rows on every ring page (Oura, Ultrahuman, RingConn, Galaxy Ring, Circular).
| Attribute | Value | Source / note |
|---|---|---|
| Materials | High-grade titanium with coating; non-allergenic clinical-grade biocompatible inner epoxy (guide) | Circular Ring 2 user guide |
| Width | 7.8 mm | Shop “by the numbers”; user guide dimensions |
| Thickness | 2.55 mm | Shop; user guide |
| Weight | 3 g (shop also uses “four grams” in one marketing line — we use the 3 g spec block) | Shop spec block; user guide |
| Sizes | US 6–14 (nine sizes) | Shop; user guide |
| Finishes | Silver, Obsidian, Gold, Rose Gold (shop). Sensors/battery identical across finishes. | shop.circular.xyz/products/circular-ring-2 |
| Battery (OEM) | Shop spec: 8 days power mode, ~5 days performance. Shop FAQ (2026-09-19 evening): around eight days power / four to five performance. User guide: up to 7 days (power mode); 14.5–21.5 mAh Li-Ion. | Circular shop spec + FAQ; user guideDo not average 8 and 7, or 5 and 4–5. Quote the page you are citing. |
| Charging (OEM) | Shop: 30 minutes to full. User guide: up to 60 minutes from empty; 5 V; first-use calibration ≥45 minutes at 100%. | Shop; user guide §07 |
| Charging case (OEM) | Wireless charging case included; 700 mAh pack in the guide; size-specific; extra Case 2 sold for $39 on the shop. Charger is not waterproof. | Shop; user guide |
| Water resistance | Not published | User guide — Waterproof / spec; shop FAQ |
| Sensors | Single-lead ECG; 3-axis accelerometer; digital temperature; 3-LED oximeter (IR, red, green) | User guide — Ring Sensors; shop |
| Sleep tracking | Four-stage sleep, breathing rate, blood oxygen, morning score (shop). Up to 7 days flash memory depending on use (guide). | Shop; user guide |
| Activity / fitness | Activity and energy; live HR / SpO2 / temperature on demand (shop). Tight-grip sports can impair PPG (guide). | Shop; user guide accuracy notes |
| App | Circular app (iOS App Store, Google Play). Pair as “Gen 2” in the guide’s setup copy. | User guide |
| Subscription / data access | No mandatory subscription for core features (shop FAQ). Some advanced screens are premium and can be unlocked with coins earned by wearing the ring. | Shop FAQ |
| Phone platforms | iPhone (App Store) and Android (Google Play). Exact OS version floors not published on the fetched guide/shop pages. | User guide; shop |
| Wireless | Bluetooth Low Energy 4.2 to 5.0 (guide); airplane mode listed on the shop spec block | User guide; shop |
| On-ring storage | Flash ROM up to 7 days depending on type and frequency of use | User guide |
| US price (dated) | $299 sale / $349 list on shop.circular.xyz, 2026-09-19 | Circular Ring 2 shop |
| Price band | Mid, no mandatory data subscription | Derived from dated shop |
| Announced | Current Circular shop SKU as of 2026-09-19 (no Ring 3 retail spec page) | shop.circular.xyz |
| Availability | Shop live with worldwide shipping copy and US HSA/FSA note (accessed 2026-09-19) | Circular shop |
Circular Ring 2 extras
Unique to this line or SKU. Other rings keep the first table aligned and swap this extras list.
| Attribute | Value | Source / note |
|---|---|---|
| ECG intended use | Single-lead spot recording (~40 s). User guide: wellness tracking only; not a medical device or diagnostic tool. Consult a clinician for medical concerns. | User guide — ECG |
| Blood pressure (shop) | Shop: pulse-transit-time estimate calibrated monthly to your own cuff. Shop FAQ: wellness trend, not a diagnosis. | Circular shop |
| Shop vs guide battery | Not published | Shop spec + FAQ + user guide, 2026-09-19 evening re-pull |
| Water vs 100 m rings | 50 m / 30 min in the guide vs Oura/RingConn 100 m claims. Different product class. | User guide |
| Older Circular SKUs | Not published | shop.circular.xyz/collections/all; Circular user-guide picker |
| FCC / model | FCC ID 2BOAM-CR2; model CR2; Japan MIC 218-250745 (user guide regulatory block, re-opened 2026-09-19 evening) | Circular Ring 2 user guide — Regulatory |
Overview
Circular Ring 2 is the current Circular: 7.8 × 2.55 mm, 3 g titanium, sizes 6–14, ECG + optional cuff-calibrated BP trends, no mandatory sub. Water is 50 m / 30 min in the guide (the same spec block also prints a stray “Up to 5m” line — keep both).
Sensors, sleep, and activity
ECG electrodes, PPG (IR/red/green), temperature, accelerometer. Four-stage sleep on the shop. Guide: ECG is wellness only.
Battery and charging
Cite the OEM tables. Shop spec 8 / ~5 days and 30 minutes; shop FAQ also says four to five days in performance mode; guide up to 7 days and 60 minutes. Case is size-specific and not waterproof.
App, subscription, and platforms
Circular app, iOS and Android. Core features included; coin-unlock language on the shop. No invented OS floors.
Price
$299 sale / $349 list on 2026-09-19. Date it.
Sources
- Circular shop — Ring 2 — accessed 2026-09-19
- Circular — Ring 2 user guide — accessed 2026-09-19
Frequently asked questions
Does it need a subscription?
Circular’s shop FAQ: no mandatory subscription for core features. Some advanced screens use coins you earn by wearing the ring. Date that policy if it changes.
Is the ECG medical-grade?
The shop uses strong clinical language. The user guide is the intended-use document we follow: wellness tracking only, not a medical device or diagnostic tool. We do not upgrade that to a diagnosis claim.
Why do you list two battery numbers?
Because Circular publishes more than one table. Shop spec: 8 days / ~5 days performance / 30 minutes. Shop FAQ (evening re-pull): around eight / four to five days. Guide: up to 7 days / 60 minutes from empty. Averaging them would be invented.
iPhone or Android?
Both, per the user guide (App Store and Google Play). Exact OS version floors were not on the pages we opened.
Official product page: Circular Ring 2. Specs: Circular Ring 2 specs.