Updated October 1, 2026 · ThriveCue Editorial Team
Circular vs Ultrahuman Amazon
What sets them apart
| Compare |  Circular |  Ultrahuman Amazon |
|---|---|---|
| Price from | $349 | €379 |
| Membership per month | $0 | €0 |
| Battery life | 8 days | 15 daysHigher |
| Water resistance (m) | 50 | 100Higher |
| Markets | LV, JP, IN, TH, CN, ID, VN, HK, SG, TW, KR, PH, MY, BD, KH, AL, DE, AD, AM, AT, BY, BE, BA, BG, CY, VA, HR, DK, ES, EE, FI, GE, GI, GR, GL, GG, HU, IM, AX, FO, IE, IS, IT, JE, XK, LI, LT, LU, MK, MT, YT, MD, MC, ME, NO, NL, PL, PT, CZ, RE, RO, SM, RS, SK, SI, SE, SJ, TR, UA, FR, IL, FJ, MX, PF, PG, AZ, LA, LB, LK, MN, MO, NP, PK, PS, TJ, UZ, AR, BR, CI, CM, CO, CV, DZ, EC, EG, GA, GF, GH, GM, GN, GW, LY, MA, MG, ML, NE, NG, PE, SN, TN, UY, ZA, BL, MF, MQ, PM, CL, CA, SC, BH, OM, SA, QA, AE, KW, MM, JO, AU, NZ, CH, GB, USCovers more | IN, AE, US, GB, BE, CZ, DK, FR, DE, IE, IT, NL, PL, ES, BG, HR, EE, GR, HU, LV, LT, LU, MT, RO, SK, SI, AT, PT, SE |
Same on both: Platforms (iOS, Android), Warranty (1 year).
We earn a commission when you sign up through links on this site. Partner status can affect where a brand appears in our rankings.
Key differences
- Ultrahuman Amazon scores higher overall: 9.1 vs 8.8.
- Battery life is higher at Ultrahuman Amazon: 15 days vs 8 days.
- Water resistance (m) is higher at Ultrahuman Amazon: 100 vs 50.
- Support channels: only Ultrahuman Amazon offers Phone, Community.
- Circular is available in 101 more countries.
- Health sensors: only Circular offers Ecg, Blood pressure.
- Markets: only Circular offers JP, TH, CN.
Our verdict on each
Circular
Circular suits anyone who wants a smart ring without a recurring subscription, and it holds the top spot on membership cost with a monthly fee of $0. The catch is endurance: 8 days of battery sits below what rivals manage.
Ultrahuman Amazon
Ultrahuman suits readers who want sleep and recovery readings from a ring and would rather not pay a monthly fee after buying it. The ring costs €379 once, tracks sleep, heart rate, blood oxygen, skin temperature and HRV, and works with iOS and Android.
Score breakdown
| Area | Circular | Ultrahuman Amazon |
|---|---|---|
| Cost | 8.8HigherEntry price of $349 ranks 29 of 31, and the membership costs $0. | 8.7The cost part scores 8.7. The Ultrahuman ring is an upfront payment of €379 with a €0 monthly membership, so nothing stacks up each month. |
| Offer | 8.8Membership fee of $0 places it 1 of 21 on that measure. | 9.4HigherThe offer part scores 9.4, pairing 15 days of battery with 100 metres of water resistance and 1 year of cover. |
Which one suits you
Pick Circular if markets matter most.
Pick Ultrahuman Amazon if offer, battery life, and water resistance (m) matter most.
Where these facts come from
Circular
- circular.xyz: 7 facts, checked September 30, 2026
- shop.circular.xyz: 5 facts, checked September 30, 2026
Ultrahuman Amazon
- ultrahuman.com: 12 facts, checked September 30, 2026
How they place
| Ranking | Circular | Ultrahuman Amazon |
|---|---|---|
| Smart rings | 12 of 14 | 1 of 14 |
Every fact side by side
| Fact | Circular | Ultrahuman Amazon |
|---|---|---|
| Products | Smart ring | Smart ring |
| Health sensors | Heart rate, Spo2, Ecg, Skin temperature, Hrv, Sleep, Blood pressureCovers more | Heart rate, Spo2, Skin temperature, Hrv, Sleep |
| Legal entity | Circular Health Limited | Ultrahuman Healthcare Private Limited |
| Headquarters | France | India |
| Support channels | Email, Chat, Help centre | Email, Chat, Phone, Help centre, CommunityCovers more |
Where each stands against the rest
| Fact | Circular | Ultrahuman Amazon | Median |
|---|---|---|---|
| Battery life | 8 daysbelow the median | 15 daysabove the median | 14 days |
| Water resistance (m) | 50at the median | 100above the median | 50 |
| Warranty | 1 yearat the median | 1 yearat the median | 1 year |
Median across 27 listed brands.
Pros and cons
Circular
Pros
- No recurring membership charge at $0, which ranks 1 of 21 brands.
- Entry price of $349 is a single hardware cost rather than a package that hides a subscription.
- Water resistance of 50 metres suits swimming, showering and general wear.
Cons
- Battery life of 8 days ranks 16 of 23 brands, so charging is more frequent.
- The entry price of $349 sits at 29 of 31 brands, so the hardware itself is not the cheapest.
- Support runs on email, chat and help centre only, with no phone line listed.
Ultrahuman Amazon
Pros
- The monthly membership on the Ultrahuman plan is €0, so the ring is a single purchase rather than a subscription you keep paying for.
- Support runs on email, chat and phone, which is wider than an email address alone.
- The app runs on iOS and Android, so the system on your phone does not narrow your choice.
Cons
- The Ultrahuman entry price of €379 sits above Oura at €265.30, so the upfront spend is the biggest reason to pause.
- Battery life of 15 days ranks 7 of 23, so recharging stays part of the weekly habit.
- Warranty cover runs 1 year, which is short for hardware worn every night and never taken off.
Who each suits
Circular
Who it suits
- Buyers who want a ring and no monthly membership, given the fee of $0.
- People who care about durability over battery, with resistance of 50 metres and a 1 year warranty.
- Senders who travel often, since Circular Health Limited ships across LV, JP and IN.
Who should look elsewhere
- Battery-first buyers, who should look at Oura, where the entry price starts at €265.30.
- Shoppers who want a ring plus a watch, since Amazfit and Samsung both list wider product ranges while Circular sells smart ring only.
Ultrahuman Amazon
Who it suits
- Readers who want sleep, heart rate and HRV data from a ring with no recurring membership charge.
- Swimmers and gym users, since water resistance reaches 100 metres.
- People who want to talk to someone when sizing or delivery goes wrong, since support runs on email, chat and phone.
Who should look elsewhere
- Oura buyers on a tight budget, because the Ultrahuman entry price of €379 is higher than €265.30.
- Amazfit shoppers who want more than one kind of device, since Ultrahuman covers smart ring alone while Amazfit lists smartwatch, fitness tracker and smart ring.
- Samsung shoppers who want a watch alongside a ring, since Samsung lists smartwatch and smart ring.
Current offers
Ultrahuman Amazon
Current offer
Free trial
30-night risk-free trial on Ring AIR: 30 nights
Free returns; ring must be returned with all original accessories in original packaging within 30 days of delivery; page states no end date
Source, checked September 30, 2026
Country by country
| Country | Circular | Ultrahuman Amazon |
|---|---|---|
| Aland Islands | Yes | No |
| Albania | Yes | No |
| Algeria | Yes | No |
| Andorra | Yes | No |
| Argentina | Yes | No |
| Armenia | Yes | No |
| Australia | Yes | No |
| Azerbaijan | Yes | No |
8 of 130 countries where either is available.
Questions about each
Circular
How much does the Circular ring cost?+
The entry price is $349, charged for the hardware itself. There is no joining fee to use it, since the membership costs $0. Readers comparing total ownership over several years will find the hardware cost is front loaded rather than spread across a subscription.
Is there a membership fee for Circular?+
No monthly membership is charged, as the membership costs $0. That places Circular 1 of 21 brands on that measure. It is the main reason to pick this ring over rivals that tie the app to a recurring plan.
Ultrahuman Amazon
What does the Ultrahuman ring cost to buy?+
The Ultrahuman ring starts at €379. That is the entry price for the hardware and it is paid as a single payment rather than in instalments. On top of it, the monthly membership on the Ultrahuman plan is €0, so the number you start with is close to the number you pay.
Is there a monthly fee after I buy the ring?+
No recurring charge. The monthly membership on the Ultrahuman plan is €0, so once the ring is paid for at €379 there is no standing subscription to cancel. Readers who dislike watching a payment leave their account every month for wearable data can buy it and set it aside.