Smart Rings / Ultrahuman Ring PRO (2026) vs Circular Ring 2 (2025)
Ultrahuman Ring PRO (2026) vs Circular Ring 2 (2025)
Ultrahuman Ring PRO (2026)
15-day battery and no subscription — until you notice AFib is a paid add-on.
Wins overall by 0.7 points
Quick Verdict
The Ultrahuman Ring PRO (2026) is the stronger all-round pick, ahead by 0.7 points. 15-day battery and no subscription — until you notice AFib is a paid add-on.
The Ultrahuman Ring PRO (2026) and Circular Ring 2 (2025) are both closely matched smart Ring models, and the Circular Ring 2 (2025) is $180 cheaper than the Ultrahuman Ring PRO (2026) ($299 vs $479). On App & Data, the Ultrahuman Ring PRO (2026) leads (7.5 vs 4.5/10) — app stability, insight depth, platform parity and whether you can get your history out. On Durability, the Ultrahuman Ring PRO (2026) leads (7.5 vs 5.5/10) — finish scratch resistance, water rating in practice, and whether the finish is warrantied. On Battery Life, the Ultrahuman Ring PRO (2026) leads (9.5 vs 8.0/10) — real days between charges with continuous sensing on, plus what the charging case adds. Overall, the Ultrahuman Ring PRO (2026) scores 7.8/10 across our 8 scoring categories versus 7.1/10 for the Circular Ring 2 (2025). Below, we break down the full spec sheet, category-by-category scores, and exactly who should buy which one.
Side-by-Side Comparison
| Spec | Ultrahuman Ring PRO (2026) | Circular Ring 2 (2025) |
|---|---|---|
| Price | $479.00 | $299.00 |
| Release Year | 2026 | 2025 |
| Battery Life (claimed) (days) | 15✓ | 8 |
| Battery, In Practice | Ultrahuman claims up to 15 days in standard mode, and 'up to 45 days' only when you count recharges held in the PRO charging case. Independent long-term battery testing under continuous SpO2 and temperature sensing was not available at the time of writing — the ring has only been shipping in the US for weeks. | 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. |
| Subscription | No subscription for your core data — sleep, recovery, movement, stress and circadian insights are included. But the clinical-sounding features are sold as optional annual PowerPlugs at $24-$39 each, and AFib detection is one of them. 'No subscription' and 'AFib included' are not the same sentence. | No mandatory subscription today; core features come with the ring, and some advanced screens are unlocked with in-app coins earned by wearing it. Circular has said a premium tier covering blood glucose and blood pressure is coming, with neither price nor date published — so the no-subscription position is provisional, not guaranteed. |
| 3-Year Cost of Ownership ($) | 479 | 299✓ |
| Sizes Offered | US 5-14, no half sizes. Ultrahuman states its sizes may differ slightly from standard US ring sizes. | US 6-14 |
| Sizing Kit | Complimentary sizing kit with plastic sizers in sizes 5-14, shipped with the order. | 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. |
| Returns & Size Exchange | Not published on the pages reviewed. Check Ultrahuman's US terms at checkout before ordering a size. | 14-day no-questions-asked return policy, 1-year warranty (2 years in the EU). |
| Measured vs Inferred | PPG optical sensing plus skin temperature and motion, processed by an on-ring dual-core chip with on-chip machine learning. AFib detection, metabolic insight for GLP-1 users, ovulation tracking, snoring analysis and migraine insight are all software PowerPlugs layered on the same sensors — buying more PowerPlugs does not add hardware. | 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. |
| FDA Clearance | Not published by Ultrahuman for the Ring PRO or its AFib PowerPlug in the sources reviewed. Coverage of the US relaunch describes AFib detection as a paid PowerPlug and does not cite an 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. |
| Water Rating | 100m / 328ft | 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 |
| Phone Support | iOS and Android | iOS and Android |
| Charger & Data Export | Standard charger and a 1m USB-C cable in the box; the PRO Charging Case is a $100 accessory (bundled into the $479 configuration). Export: not published by the manufacturer, though 250 days of history is retained on the ring itself. | 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. |
| Warranty | 12 months | 12 months |
| Colors | Bionic Gold, Space Silver, Aster Black, Raw Titanium | Obsidian Black, Silver, Gold, Rose Gold |
Category Scores
Subscription Freedom
The Circular Ring 2 (2025) leads clearly here, 8.0 against 7.0 — a 1.0-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 Ultrahuman Ring PRO (2026) does not close the gap elsewhere.
Sleep Tracking
The Ultrahuman Ring PRO (2026) leads clearly here, 8.0 against 7.0 — a 1.0-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) is marginally ahead, 8.5 to 8.3. A gap this small rarely decides a purchase on its own, though it counts if what the sensors genuinely measure — heart rate, SpO2, temperature, ECG — rather than infer is your priority.
Battery Life
The Ultrahuman Ring PRO (2026) leads clearly here, 9.5 against 8.0 — a 1.5-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 Circular Ring 2 (2025) does not close the gap elsewhere.
Sizing & Fit
The Ultrahuman Ring PRO (2026) and Circular Ring 2 (2025) are level here, at 8.0/10 each. how many sizes exist, how good the sizing kit is, and how forgiving the exchange policy is is not what separates these two — look to the categories where the scores diverge.
App & Data
The Ultrahuman Ring PRO (2026) leads clearly here, 7.5 against 4.5 — a 3.0-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 Ultrahuman Ring PRO (2026) leads clearly here, 7.5 against 5.5 — a 2.0-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 6.5 — a 0.5-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 Ultrahuman Ring PRO (2026) does not close the gap elsewhere.
Best For
Choose the Ultrahuman Ring PRO (2026) if…
- • App & Data matters most to you — the Ultrahuman Ring PRO (2026) scores 7.5/10 here (app stability, insight depth, platform parity and whether you can get your history out).
- • Durability matters most to you — the Ultrahuman Ring PRO (2026) scores 7.5/10 here (finish scratch resistance, water rating in practice, and whether the finish is warrantied).
- • Battery Life matters most to you — the Ultrahuman Ring PRO (2026) scores 9.5/10 here (real days between charges with continuous sensing on, plus what the charging case adds).
- • Sleep Tracking matters most to you — the Ultrahuman Ring PRO (2026) scores 8.0/10 here (sleep staging depth, overnight accuracy and how usable the morning report is).
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).
- • You want to spend less — it's $180 cheaper.
Pros & Cons
Ultrahuman Ring PRO (2026)
Pros
- +15-day claimed battery and 45 days with the case — nothing else here is close
- +250 days of on-ring storage means it keeps working through a phone loss, a trip or a long stretch offline
- +ProRelease cutaway is the only answer any of these brands has to a swollen finger and a ring that cannot come off
- +Core sleep, recovery and stress data carries no recurring fee
Cons
- −AFib detection is a paid annual PowerPlug ($24-$39), so the 'no subscription' pitch does not cover the feature people most want
- −Ship dates keep moving — TechTimes said 20 June, gadgetsandwearables said 10 August, and Ultrahuman's own page now says 15 September onwards
- −Ultrahuman was banned from US import in October 2025 over Oura's patent; the Ring PRO is a redesign, and that history is a real supply risk
- −$479 as configured is the most expensive ring here, and the $399 version does not include the charging case
- −No FDA clearance is published for the AFib PowerPlug in the coverage of the US relaunch
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
Shop by Need
FAQs
Is the Ultrahuman Ring PRO (2026) or Circular Ring 2 (2025) better overall?+
Based on our 8-category scoring, the Ultrahuman Ring PRO (2026) 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 App & Data, the Ultrahuman Ring PRO (2026) or the Circular Ring 2 (2025)?+
The Ultrahuman Ring PRO (2026) scores higher on App & Data (7.5/10 vs 4.5/10) — app stability, insight depth, platform parity and whether you can get your history out.
Which is better for Durability, the Ultrahuman Ring PRO (2026) or the Circular Ring 2 (2025)?+
The Ultrahuman Ring PRO (2026) scores higher on Durability (7.5/10 vs 5.5/10) — finish scratch resistance, water rating in practice, and whether the finish is warrantied.
Which is better for Battery Life, the Ultrahuman Ring PRO (2026) or the Circular Ring 2 (2025)?+
The Ultrahuman Ring PRO (2026) scores higher on Battery Life (9.5/10 vs 8.0/10) — real days between charges with continuous sensing on, plus what the charging case adds.
Which is better for Subscription Freedom, the Ultrahuman Ring PRO (2026) or the Circular Ring 2 (2025)?+
The Circular Ring 2 (2025) scores higher on Subscription Freedom (8.0/10 vs 7.0/10) — how much of the ring keeps working with no recurring payment — the category's defining trap.
Is the Ultrahuman Ring PRO (2026) worth the price difference over the Circular Ring 2 (2025)?+
The Circular Ring 2 (2025) is the cheaper option at $299 versus $479. Whether the pricier model is "worth it" depends on how much you value its lead in App & Data.
What's the warranty on the Ultrahuman Ring PRO (2026) vs the Circular Ring 2 (2025)?+
The Ultrahuman Ring PRO (2026) ships with a 12-month warranty; the Circular Ring 2 (2025) 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 2 (2024) — $269.00
Specifications and prices for both products last verified . Scores are calculated from published specifications — see how we compare products.