Start with the entry price, then add the membership
The hardware price is the number most listings lead with, and it is where the cheapest and dearest rings in our data sit furthest apart: entry prices run €70.15 to €379. That spread is wide enough that two rings can look like the same purchase and cost very different amounts over a few years.
Amazfit is the value case in this group, with prices from $79.99. Ultrahuman Amazon sits at the opposite end, with prices from €379. Oura falls between them, at €265.30, and Samsung at $299.99.
The recurring cost is the membership, and this is where the comparison often changes. Monthly fees across our data run €0 to €8.74. Oura charges €5.99 each month, while Samsung and Ultrahuman Amazon list $0 and €0. A ring with a low entry price and a monthly fee can overtake a dearer ring with no fee, so add both numbers before you decide. The Amazfit review and the Oura review set out what each one includes.
Battery life is the number you will feel every day
A ring that runs out every other night produces gaps, and gaps weaken any trend you are trying to read. Battery life in our data runs 2 to 21 days, so the field stretches from short spans to a multi week figure.
Amazfit leads this group on battery, with 21 days on the figure listed for its balance model. Ultrahuman Amazon is close behind at 15 days, Samsung sits at 14 days, and Oura gives 6 to 9 days. If you already charge nightly or more often, battery matters less. If you sleep through the week without thinking about a charger, weight it heavily.
Oura is the clearest case for reading the range rather than a single number, since its 6 to 9 days is stated as a span rather than a promise of a single night. Check the Samsung review and the Ultrahuman Amazon review for how each of those brands handles charging.
Compare sensors by what you want to track
Sensor lists are the easiest place to be impressed by a long line of words. The useful question is simpler: which measurements do you actually plan to act on, and does the ring take them without a subscription.
Samsung lists the widest set in this group with heart rate, spo2 and ecg. Amazfit covers heart rate, spo2 and sleep. Oura lists heart rate, spo2 and hrv, and Ultrahuman Amazon lists heart rate, spo2 and skin temperature.
Two details deserve attention. A GPS reading inside a ring is unusual, and it appears in the Amazfit and Samsung lists, so treat it as a bonus feature rather than a core expectation for a finger worn device. Skin temperature appears across every brand here, which makes it a shared baseline rather than a differentiator. Where a reading sits behind a membership, the membership figure in the previous section is the deciding number.
Where the company sits and where the ring can be bought
Registration details decide whether a brand is straightforward to deal with in your market, and the legal entity behind the product is worth reading once before you order.
Oura is run by Oura Health Oy, registered in FI. Amazfit belongs to Zepp Health Corporation, Ltd., registered in HK, and Ultrahuman Amazon is operated by Ultrahuman Healthcare Private Limited, registered in IN. Samsung is sold by Samsung Electronics America, Inc. Only Oura and Ultrahuman Amazon list specific sales markets, and both cover GB, so UK buyers have an established route with either.
Amazfit also makes smartwatches, fitness trackers, chest straps and smart scales, and Samsung makes smartwatches. If you already wear one of those brands, the shared app can be the reason to stay inside it. If you want a ring and nothing else, Oura and Ultrahuman Amazon build only smart rings.
Warranty, water resistance and where help comes from
Every brand in this group rates its rings to 100 m of water resistance, so swimming and showering are not the point of difference. Warranty length is. Oura covers 1 to 2 years, while Samsung offers 1 year, so a ring is covered for longer with Oura than with Samsung.
Support reach varies more. Oura offers help centre, chat and email. Samsung offers help centre, chat and phone. Amazfit offers email and help centre, which is a thinner list, and is the point at which a buyer with a fitting or battery question may prefer a larger maker. Ultrahuman Amazon has no support channels listed here, so check its own pages before buying.
All of them work on iOS and Android phones, so platform is not a filter for anyone choosing between them. The Smart rings rankings pull these figures together, and the Oura review and Samsung review cover the fit and day to day experience in more depth.
Shortcuts if you want a fast answer
For the lowest outlay and the longest battery, Amazfit is the pick, at $79.99 with 21 days of battery. The trade-off is a shorter support list and a wider device range rather than ring specialism.
For a ring built only as a ring, with the broadest membership funded sensor set and multi year warranty, Oura is the pick at €265.30 plus €5.99 a month. The trade-off is the shortest battery span in the group.
Samsung suits buyers already inside its ecosystem, at $299.99 with $0 membership and the longest sensor list here. Ultrahuman Amazon suits buyers who want no membership at all, at €379 with €0 and 15 days of battery.
Honourable mentions: RingConn, ERA-FIT, METZ, Circular and SleepOn, which broaden the same price and battery spread covered here.