Amazfit Helio Ring vs Oura Ring 5: the cheap no-fee ring against the one with the evidence

The verdict

We are not going to pick a winner on hardware price. Ring prices move daily, so the cards on this page read the live Amazon listing and the writing stays out of it. The ordering on the day we checked is worth saying once, because it is the reason this comparison exists at all: the Helio Ring sat in a different bracket from the Ring 5, well below it, and below every RingConn too.

The fee, which is the whole argument

Everything else on this page is a detail hanging off one number. Oura's membership is $5.99 a month or $69.99 a year in the US, with one month included and no lifetime option (Oura Support). Amazfit's Helio page says “No Subscriptions Required” and the Amazon listings say “Subscription Free”.

There is one asymmetry hiding inside Amazfit's zero, and we would rather name it than pretend the Helio is unconditionally free. Footnote 3 on Amazfit's own Helio page reads “Readiness insights require subscription to Zepp Aura,” while the same page lists Zepp Aura as “now free for Amazfit Helio Ring users.” So the headline readiness score sits on a plan Amazfit bundles rather than on no plan existing. That is a condition Amazfit controls and can revisit. RingConn, by contrast, sells no paid tier to withdraw - which is why the third column in the table above is the quiet winner of this section.

Evidence: a research record against nothing

This is where Oura earns the fee, if anything does. Oura's previous generations have been measured against laboratory references repeatedly, and mostly by people with no stake in the answer: nocturnal heart rate and HRV against ECG (Cao et al. 2022), a Gen3 against multi-night ambulatory polysomnography (Svensson et al. 2024), a meta-analysis against medical-grade sleep studies (Khan et al. 2025), finger rings inside a clinical sleep lab (Herberger et al. 2025) and overnight HR and HRV against a Polar H10 chest strap (Dial et al. 2025).

For the Amazfit Helio Ring we found nothing. No peer-reviewed study, no preprint, no independent comparison against an ECG, a chest strap or a sleep lab. That is not an accusation - it is the normal state of a new ring from a mainstream brand - but it is the single biggest difference between these two products, and it is why the Helio scores 2 out of 10 for evidence on our rubric while the Ring 5 scores 8.

What each ring shows you for free

A ring you will not pay a fee for and a ring you will are not really competing on sensors; they are competing on what the app puts behind glass. Oura is explicit: without an active membership you keep the three daily scores (Readiness, Activity and Sleep), ring battery, basic profile, app settings and the Explore content, and that is it. No trends, no HRV chart, no temperature history - and, as our page on Oura HRV in Apple Health sets out, HRV is not part of the Apple Health integration either, so there is no free side door.

Amazfit puts the whole feature list in the free Zepp App: readiness, sleep stages and naps, sleep breathing quality, sleep HRV and resting heart rate, SpO2, stress, PAI, menstrual cycle tracking and four sports modes, with EDA emotion monitoring listed as arriving by software update. The catch is the footnote above, not a paywall in front of the nightly data.

The practical way to read that: the Helio Ring gives you more numbers for nothing, and the Oura gives you better-checked numbers for money. Which of those two sentences sounds like your problem is the whole decision.

Battery: four days against six to nine

Amazfit claims “Up to 4 days” in its own “Typical Usage Scenario” - and that scenario has heart rate, assisted sleep and stress monitoring on with blood oxygen off, which is worth knowing before you switch SpO2 on and wonder where the fourth day went. There is no charging case; the box holds the ring, a wireless charger and the manual, and Amazfit's “Theoretical Charging Duration” is “Approx. 1 hour, 40 minutes.”

Oura claims 6-9 days “depending on ring size and usage” and also ships without a case. So this is four days against six to nine, with both rings asking you to remember a cable. Neither is in the same conversation as RingConn's 10-12 days plus a case; that gap is the subject of smart ring battery life, and the charging-case question is in chargers and charging cases.

Sizes: three against eight

The Helio Ring exists in sizes 8, 10 and 12 only, two sizes apart, at 3.65-3.82 g. If your finger is a 9, an 11, or anything below 8, Amazfit does not make a ring for you, and no amount of price advantage fixes that. Amazfit does not list a sizing kit on the product page; a separate Helio sizing kit is sold on Amazon.

Oura Ring 5 runs sizes 6-13 - narrower than the Ring 4's 4-15, which still matters if you are at either extreme - and Oura's kit is free on its own store and sold on Amazon with a matching purchase credit. For anyone at the ends of the range, large and small smart ring sizes is the page that covers who actually serves you, and the sizing guide covers getting the size right the first time.

Side by side

Two rows deserve a note. On water, Amazfit cites 10 ATM against a watch standard (ISO 22810:2010) and still advises taking the ring off for hot showers and saunas; Oura quotes 100 m and IP68. Both are far past anything a shower asks, and the real caveats are in is a smart ring waterproof. On phones, both work with iPhone and Android - the Zepp App needs Android 7.0 or iOS 14.0 and above - so unlike the Galaxy Ring, neither of these locks you to a platform.

Buying, warranty and the patent case

The Helio Ring is sold on Amazon as three separate listings, one per size, rather than one listing with a size picker. That is a small thing that trips people up: if you land on the size 8 listing and your finger is a 12, the ring looks unavailable when it is simply a different page. Oura's US warranty runs one year with batteries excluded as consumables, and Oura states HSA/FSA eligibility on the Ring 5 page - see HSA and FSA eligibility for how that works in practice, and warranty and returns for the brand-by-brand terms.

One piece of legal background, because it used to be a reason to hesitate: Amazfit's parent, Zepp Health, was a respondent in Oura's ITC patent action. A joint request to terminate Zepp from that investigation was filed in July 2026 on the basis of a settlement, approved by the administrative law judge and confirmed by the Commission on August 11, 2026, with terms not made public (Gadgets & Wearables). In plain terms, the Helio Ring is not under an exclusion-order cloud in the US the way the Ultrahuman Ring AIR still is.

Who should buy which

Buy the Oura Ring 5 if you are going to act on the numbers - training, a sleep problem you are working on with a clinician, a cycle you are tracking - and you want the device whose predecessors have been held up against ECG and polysomnography. Price the membership into the decision honestly: over a few years it costs more than the ring did, and it never stops. If you own an Apple Watch already, read is an Oura Ring worth it with an Apple Watch first, because the two features that would justify owning both devices are the membership-gated ones.

Buy the Amazfit Helio Ring if you want a ring-shaped sleep and readiness tracker from a brand with a real support line at the lowest cost of entry here, you are a size 8, 10 or 12, and you treat the output as a trend line rather than a measurement. Our Amazfit Helio Ring review is the long version, and Helio vs RingConn Gen 2 is the comparison that matters more than this one if you have already ruled out paying a fee.

Buy neither if what you actually want is the no-fee position without the compromises: that is the RingConn Gen 2, with 10-12 days, a case, nine sizes and a chest-strap preprint of its own (Tao et al. 2026, not peer-reviewed). And if you would rather not have anything on your finger at all, the no-fee options that aren't rings are ranked in best fitness trackers with no subscription.