Smart Rings / Circular Ring 2 (2025) vs Oura Ring 5 (2026)
Circular Ring 2 (2025) vs Oura Ring 5 (2026)
Circular Ring 2 (2025)
The only FDA-cleared AFib ring — attached to the buggiest app in the category.
Wins overall by 0.0 points
Quick Verdict
This is close. The Circular Ring 2 (2025) edges ahead by 0.0 points, but that margin is inside the noise — the Oura Ring 5 (2026) is a defensible pick on its own terms. The best sleep tracking on a finger, rented to you at $5.99 a month forever.
The Circular Ring 2 (2025) and Oura Ring 5 (2026) are both closely matched smart Ring models, and the Circular Ring 2 (2025) is $100 cheaper than the Oura Ring 5 (2026) ($299 vs $399). On Subscription Freedom, the Circular Ring 2 (2025) leads (8.0 vs 2.0/10) — how much of the ring keeps working with no recurring payment — the category's defining trap. On App & Data, the Oura Ring 5 (2026) leads (9.0 vs 4.5/10) — app stability, insight depth, platform parity and whether you can get your history out. On Sleep Tracking, the Oura Ring 5 (2026) leads (9.5 vs 7.0/10) — sleep staging depth, overnight accuracy and how usable the morning report is. Overall, the Circular Ring 2 (2025) scores 7.1/10 across our 8 scoring categories versus 7.1/10 for the Oura Ring 5 (2026), though the gap is close enough that your specific use case should decide it. Below, we break down the full spec sheet, category-by-category scores, and exactly who should buy which one.
Side-by-Side Comparison
| Spec | Circular Ring 2 (2025) | Oura Ring 5 (2026) |
|---|---|---|
| Price | $299.00 | $399.00 |
| Release Year | 2025 | 2026 |
| Battery Life (claimed) (days) | 8 | 9✓ |
| Battery, In Practice | Circular publishes two numbers, not one: 8 days in power mode and 5 days in performance mode — performance mode is the one that samples more often. Tom's Guide's tester got a week or more in practice. | Oura's own claim is a range, 'up to 6-9 days depending on ring size and usage' — the small sizes sit at the bottom of it because the battery is physically smaller. TechCrunch's reviewer was at roughly 25% after five days of continuous wear. Charging takes about 80 minutes. |
| Subscription | No mandatory subscription today; core features come with the ring, and some advanced screens are unlocked with in-app coins earned by wearing it. Circular has said a premium tier covering blood glucose and blood pressure is coming, with neither price nor date published — so the no-subscription position is provisional, not guaranteed. | Required in practice. $5.99/month or $69.99/year after one free month. Oura's own FAQ: without a membership 'your Oura Ring and Oura App will still function, but the insights, personal health data, and benefits you receive will be much more limited' — you keep the three headline scores and lose the 50+ metrics behind them. |
| 3-Year Cost of Ownership ($) | 299✓ | 608.97 |
| Sizes Offered | US 6-14 | US 6-13, no half sizes. Ring 4 covered 4-15; Oura told TechCrunch the smaller form factor is harder to manufacture at the extremes, so small and large fingers lose the option entirely. |
| Sizing Kit | Two routes: a camera-and-credit-card digital sizing flow that needs no kit at all, or a $5 physical replica-ring kit. This is the only brand here that lets you skip the kit wait entirely. | Free plastic sizing kit ships before the ring. Oura instructs you to wear the sizer for at least 24 hours including overnight, so the kit round trip adds roughly a week before the ring is even ordered. |
| Returns & Size Exchange | 14-day no-questions-asked return policy, 1-year warranty (2 years in the EU). | Oura does not publish a return window on its warranty page. The 1-year limited warranty explicitly excludes 'normal wear and tear, such as scratches and dents caused by everyday handling' and lists batteries as a non-covered consumable part. |
| Measured vs Inferred | The only ring in this comparison with actual ECG electrodes: a 40-second single-lead reading screened for atrial fibrillation. Everything else — the 140+ 'biosignals' across 13+ health features — is derived from the same PPG, temperature and motion stack every other ring uses. | Green and infrared LEDs for continuous heart rate and HRV; red and infrared LEDs for blood oxygen, which Oura reports as an overnight figure rather than an all-day continuous trace; NTC skin-temperature sensor; accelerometer. Readiness, Stress, Resilience and Health Radar are derived scores computed from those four signals, not separate measurements. |
| FDA Clearance | Circular states, and Tom's Guide's review confirms, that the ring is FDA-cleared to monitor for irregular heartbeats indicating AFib. That clearance covers the AFib feature, not the other 140 biosignals. | None published for the Ring 5 or its app features — Oura markets the whole product as general wellness. The Blood Pressure Signals feature announced alongside the Ring 5 is not a cuff-equivalent blood-pressure measurement. |
| Water Rating | Sources conflict: Circular's own store page lists IP68 only, while Tom's Guide's review states 50m water resistance with IP68 — either way, half the 100m rating Oura and RingConn claim | IP68 and water resistant to 100m/328ft; Oura says it is not for scuba diving |
| Phone Support | iOS and Android | iOS and Android, full feature parity |
| Charger & Data Export | Proprietary charger. Export: not published by the manufacturer. Tom's Guide reported sync failures that lost whole nights of sleep data, so what reaches the app is not always complete. | Proprietary size-specific dock in the box plus a USB-C cable — a charger made for one ring size does not fit another, so a replacement has to match your ring. Export: not published as a one-click history download; Oura documents a personal-access-token Cloud API that third-party tools use to pull history. |
| Warranty | 12 months | 12 months |
| Colors | Obsidian Black, Silver, Gold, Rose Gold | Silver, Black, Brushed Silver ($499), Stealth ($499), Gold ($499), Deep Rose ($499) |
Category Scores
Subscription Freedom
The Circular Ring 2 (2025) leads clearly here, 8.0 against 2.0 — a 6.0-point margin on how much of the ring keeps working with no recurring payment — the category's defining trap. If that is what you are buying for, the Oura Ring 5 (2026) does not close the gap elsewhere.
Sleep Tracking
The Oura Ring 5 (2026) leads clearly here, 9.5 against 7.0 — a 2.5-point margin on sleep staging depth, overnight accuracy and how usable the morning report is. If that is what you are buying for, the Circular Ring 2 (2025) does not close the gap elsewhere.
Health Sensing
The Circular Ring 2 (2025) and Oura Ring 5 (2026) are level here, at 8.5/10 each. what the sensors genuinely measure — heart rate, SpO2, temperature, ECG — rather than infer is not what separates these two — look to the categories where the scores diverge.
Battery Life
The Circular Ring 2 (2025) leads clearly here, 8.0 against 7.5 — a 0.5-point margin on real days between charges with continuous sensing on, plus what the charging case adds. If that is what you are buying for, the Oura Ring 5 (2026) does not close the gap elsewhere.
Sizing & Fit
The Circular Ring 2 (2025) leads clearly here, 8.0 against 6.5 — a 1.5-point margin on how many sizes exist, how good the sizing kit is, and how forgiving the exchange policy is. If that is what you are buying for, the Oura Ring 5 (2026) does not close the gap elsewhere.
App & Data
The Oura Ring 5 (2026) leads clearly here, 9.0 against 4.5 — a 4.5-point margin on app stability, insight depth, platform parity and whether you can get your history out. If that is what you are buying for, the Circular Ring 2 (2025) does not close the gap elsewhere.
Durability
The Oura Ring 5 (2026) leads clearly here, 8.0 against 5.5 — a 2.5-point margin on finish scratch resistance, water rating in practice, and whether the finish is warrantied. If that is what you are buying for, the Circular Ring 2 (2025) does not close the gap elsewhere.
Value
The Circular Ring 2 (2025) leads clearly here, 7.0 against 6.0 — a 1.0-point margin on what the ring delivers against its total cost of ownership, not just its sticker price. If that is what you are buying for, the Oura Ring 5 (2026) does not close the gap elsewhere.
Best For
Choose the Circular Ring 2 (2025) if…
- • Subscription Freedom matters most to you — the Circular Ring 2 (2025) scores 8.0/10 here (how much of the ring keeps working with no recurring payment — the category's defining trap).
- • Sizing & Fit matters most to you — the Circular Ring 2 (2025) scores 8.0/10 here (how many sizes exist, how good the sizing kit is, and how forgiving the exchange policy is).
- • You want to spend less — it's $100 cheaper.
- • Your main use case is no-subscription or heart-health.
Choose the Oura Ring 5 (2026) if…
- • App & Data matters most to you — the Oura Ring 5 (2026) scores 9.0/10 here (app stability, insight depth, platform parity and whether you can get your history out).
- • Sleep Tracking matters most to you — the Oura Ring 5 (2026) scores 9.5/10 here (sleep staging depth, overnight accuracy and how usable the morning report is).
- • Durability matters most to you — the Oura Ring 5 (2026) scores 8.0/10 here (finish scratch resistance, water rating in practice, and whether the finish is warrantied).
- • Your main use case is womens-health.
Pros & Cons
Circular Ring 2 (2025)
Pros
- +The only ring here with real ECG electrodes and an FDA clearance for AFib detection
- +Digital sizing by phone camera removes the one-to-two-week sizing-kit wait every rival imposes
- +$299 with no mandatory subscription, against $608.97 over three years for a base Oura Ring 5
- +Advanced screens are earned by wearing the ring rather than billed monthly
Cons
- −The app is the weak link: Tom's Guide hit sync failures that lost sleep reports outright, and could not get the ECG feature to run during testing
- −Circular has announced a future premium tier for glucose and blood pressure with no price or date, so the no-subscription promise is not locked in
- −Water rating is half the category norm, and sources disagree on whether it is 50m or IP68-only
- −Titanium finish was described as scratch-prone, and the interior sensors protrude enough to leave marks on the finger
- −Fitness tracking is thin next to Samsung and Oura — this ring is aimed at cardiac screening, not training
Oura Ring 5 (2026)
Pros
- +Genuinely the smallest ring here — 40% smaller than Ring 4 and the first Oura that does not read as a gadget on the hand
- +Sleep staging remains the reference the rest of the category is measured against
- +iOS and Android get identical features, which Samsung cannot say
- +100m water rating and a new PVD coating Oura claims is more scratch resistant than Ring 4's
Cons
- −$5.99/month forever: the real three-year price of the base finish is $608.97, more than triple a RingConn Gen 2 Air
- −Sizes 6-13 only — Ring 4 went 4 to 15, so this generation silently dropped the smallest and largest fingers
- −The premium finishes are a $100 tax for the same electronics: Stealth, Brushed Silver, Gold and Deep Rose are all $499
- −Warranty explicitly excludes scratches and dents, and the battery is listed as a non-covered consumable
- −The charger is keyed to your ring size, so it is not a part you can borrow or generically replace
Shop by Need
FAQs
Is the Circular Ring 2 (2025) or Oura Ring 5 (2026) better overall?+
Based on our 8-category scoring, the Circular Ring 2 (2025) comes out ahead overall. See the full breakdown in the scores section above — the right pick still depends on which categories matter most for your use case.
Which is better for Subscription Freedom, the Circular Ring 2 (2025) or the Oura Ring 5 (2026)?+
The Circular Ring 2 (2025) scores higher on Subscription Freedom (8.0/10 vs 2.0/10) — how much of the ring keeps working with no recurring payment — the category's defining trap.
Which is better for App & Data, the Circular Ring 2 (2025) or the Oura Ring 5 (2026)?+
The Oura Ring 5 (2026) scores higher on App & Data (9.0/10 vs 4.5/10) — app stability, insight depth, platform parity and whether you can get your history out.
Which is better for Sleep Tracking, the Circular Ring 2 (2025) or the Oura Ring 5 (2026)?+
The Oura Ring 5 (2026) scores higher on Sleep Tracking (9.5/10 vs 7.0/10) — sleep staging depth, overnight accuracy and how usable the morning report is.
Which is better for Durability, the Circular Ring 2 (2025) or the Oura Ring 5 (2026)?+
The Oura Ring 5 (2026) scores higher on Durability (8.0/10 vs 5.5/10) — finish scratch resistance, water rating in practice, and whether the finish is warrantied.
Is the Circular Ring 2 (2025) worth the price difference over the Oura Ring 5 (2026)?+
The Circular Ring 2 (2025) is the cheaper option at $299 versus $399. Whether the pricier model is "worth it" depends on how much you value its lead in Subscription Freedom.
Which is better suited to my use case?+
The Circular Ring 2 (2025) is the better fit if you mainly care about no-subscription or heart-health. The Oura Ring 5 (2026) is the better fit for womens-health.
What's the warranty on the Circular Ring 2 (2025) vs the Oura Ring 5 (2026)?+
The Circular Ring 2 (2025) ships with a 12-month warranty; the Oura Ring 5 (2026) ships with a 12-month warranty. Always confirm current terms on the manufacturer's site before buying.
Should I wait for the next model instead of buying either of these?+
If either model is more than two years old, a successor may be close — check the "Latest Model" link on each product page. Otherwise, both are current, well-supported options and there's no strong reason to wait.
Cheaper Option
RingConn Gen 3 (2026) — $349.00
Premium Option
RingConn Gen 3 (2026) — $349.00
Specifications and prices for both products last verified . Scores are calculated from published specifications — see how we compare products.