Oura Ring 5 Review

Smart rings have always made the same promise: less conspicuous, less intrusive than any other wearable. The Oura Ring 5 is the first that genuinely keeps it. At 2 g, with a profile of just 6.1 x 2.3 mm, it is barely distinguishable from a conventional piece of jewellery on the finger — even more so than the Oura Ring 4. The flat internal sensor design introduced in the previous generation carries over, and the titanium band sits very comfortably.

Placed against twelve rivals, it finished second of thirteen, just behind the equally new RingConn Gen 3. The gap is not about capability — the two are close to even on health analysis. The rival edges ahead on feature count and battery life. What keeps the Oura in contention despite that is how it wears, and what its app does with the data — provided you can live with the subscription.

The Ring 5 measures heart rate and blood oxygen through its internal sensors, records body temperature passively in the background, and monitors breathing overnight.

Sleep tracking is the headline: the results are now indistinguishable from a good smartwatch used as a reference — a meaningful statement for a device with no screen and a battery a fraction of the size. Using pulse and temperature together, the ring can also detect early signs of illness and raises a warning in the app before you might otherwise notice.

The app runs on both Android and iOS. Its full data set includes heart rate variability, estimated VO2 max and period prediction, and the feature set continues to develop, built on the accumulated data of Oura's user base.

The catch — and it is the defining catch of this product — is that without a paid monthly subscription the app shows only rudimentary vital data. The full feature set sits behind the paywall. That is a genuine philosophical difference from its closest competitor, which includes everything with the purchase.

Eight ring sizes are offered on the US 6–13 scale, and Oura's free sizing kit is the sensible way to establish which one fits the chosen finger — ring sizing cannot be adjusted afterwards. Six finishes are available: silver, black, matt black, brushed silver, gold and rose gold.

A mislaid ring can be located through its last GPS position in the app or over the Bluetooth connection. Unlike some rivals there is no light-signal option, and there is no touch control on the ring itself.

For fitness use the Ring 5 holds up well. Standard workouts are recognised automatically, and starting a session manually in the app offers a choice of more than 20 sports. The step counter measured 97.5 per cent mean accuracy in testing, with variation between repeated runs of just 0.2 percentage points — remarkably consistent for a device this small.

Swimming is fine: the ring is water-resistant to 10 ATM, equivalent to a 100 m water column.

A single charge lasted a measured 10.7 days — a strong result, achieved with the size 10 test unit; capacity varies with ring size, since a bigger ring has room for a bigger cell. Recharging takes around 1 hour 20 minutes on the charging station supplied in the box.

A transport case with built-in charging exists but is sold separately at a significant additional cost — a pointed contrast with the main rival, which includes its charging case as standard.

In the UK the Oura Ring 5 is listed on Amazon UK at £399.00 in Silver, in stock at the time of writing, with all eight sizes selectable on the listing. Use the free sizing kit before ordering rather than guessing.

Remember to factor in the subscription: without it, the ring reports only minimal data, so the real cost of ownership is the ring plus a monthly fee for as long as you use it.

The Oura Ring 5 is the most wearable smart ring yet made — slim, feather-light, comfortable enough to forget, and backed by sensors whose sleep analysis now matches a good smartwatch and a step counter that is both accurate and unusually consistent. Ten and a half days of battery and 10 ATM water resistance remove most everyday worries, and the illness early-warning feature is the kind of quiet intelligence this category promises but rarely delivers.

Second place out of thirteen reflects its two real weaknesses honestly: the charging case costs extra, and the app is heavily gated behind a subscription that its closest rival simply does not require. If you want everything included in the purchase price, the test winner is the better value. If you want the ring that most convincingly disappears on your finger — and the most polished health app in the category — this is it.