SpO2 sensors, which enable blood oxygen monitoring, were one of the major upgrades when Oura announced its third-generation smart ring. The only downside was that while the new Oura Ring had the necessary hardware, the feature itself was still in the works. Now, about nine months after its launch, Oura says blood oxygen sensing will finally be rolled out to users this week.
Blood oxygen readings have become increasingly popular when it comes to sleep tracking. It generally works by shining a red LED on your skin. The amount of light that is then reflected back is used to estimate how much oxygen is in your blood. The feature works similarly on the Oura Ring Gen 3, which uses a combination of red and infrared LED sensors. But while many devices — such as the Apple Watch and Samsung Galaxy Watch 4 — opt for sampling, the Oura Ring will continuously take SpO2 readings during sleep.
Oura says users will see their blood oxygen data in the form of two new metrics: average blood oxygen and breathing regularity. The former is a simple percentage, while the latter is intended to track “observable drops in average blood oxygen levels.” That, in turn, aims to help users see how many sleep disturbances have been detected in one night.
Both stats are enabled by default, but users can enable or disable them via the Blood Oxygen Sensing option in the main menu. The stats themselves are displayed in the Sleep tab, and suspected variations are displayed in a timeline divided into 15-minute intervals. Each interval is represented by a color-coded line – dark blue for some variations, light blue for occasional variations, and white for frequent variations.
That said, users should take these stats with a grain of salt. As with any wellness gadget, the Oura Ring is not intended to be used in a medical or diagnostic capacity. For example, while frequent sleep disturbances may require you to contact your doctor, it’s not an automatic sign that you have sleep apnea or another chronic condition. It is also not a suitable replacement for a pulse oximeter. Essentially, this kind of portable SpO2 data is a relatively passive measure that doesn’t fluctuate much on a daily basis. Features like these are more or less meant to help you track when your long-term trends deviate from your individual baseline.
Enabling the feature also comes with a few caveats. Oura specifies that blood oxygen detection will be limited to sleep sessions lasting longer than three hours. The company also says that turning on SpO2 detection will reduce the battery life of the ring. The Oura Ring Gen 3 has an estimated battery life of a week, but in the last nine months I’ve generally gotten about 4-5 days on a single charge.
Ultimately, it’s encouraging to see Oura finally deliver on many of the Gen 3’s promised features. (It also recently rolled out HR tracking for workouts, another feature that was absent at launch.) This has been especially true since Oura introduced a new $6 monthly subscription for the Gen 3, and as you’d expect, it was it’s not a popular decision among regular customers. While the pain of having to pay a subscription won’t go away, it’s a small consolation now that users are getting more of what they were initially promised.