The SpO2 sensors, which enable blood oxygen monitoring, were one of the notable upgrades when Oura announced its third generation smart ring. The only catch was that even though the new Oura Ring had the necessary hardware, the feature itself was still in the works. Now, nearly nine months after launch, Ora says the blood oxygen sensor will finally start rolling out to users this week.
Blood oximeters are becoming increasingly popular when it comes to sleep tracking. It generally works by shining a red LED light onto your skin. The amount of light that is then reflected is used to estimate how much oxygen is in the blood. The feature works similarly on the Oura Ring Gen 3, which uses a combination of red LED and infrared sensors. But while many devices — such as the Apple Watch and Samsung Galaxy Watch 4 — opt for spot check readings, the Oura Ring will take continuous SpO2 measurements while you sleep.
Ora says users will see blood oxygen data in the form of two new measures: average blood oxygen and regularity of breathing. The former is a direct percentage, while the latter is intended to track “observed decreases in average blood oxygen levels.” This, in turn, aims to help users see how many sleep disturbances were detected in a single night.
Both gauges will be on by default, but users can toggle them on or off from the blood oxygen sensing option in the main menu. The same metrics will be displayed in the Sleep tab, and suspected differences will be shown 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.
However, users should take these metrics with caution. As with any health tool, the Oura Ring is not intended for medical or diagnostic capabilities. For example, while frequent sleep disturbances may prompt you to see 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 type of wearable SpO2 data is a relatively passive metric that doesn’t fluctuate much on a daily basis. Features like this are somewhat intended to help you track when your long-term trends deviate from your individual baseline.
Enabling the feature also comes with some caveats. Oura specifies that sensing blood oxygen will be limited to sleep sessions lasting longer than three hours. The company also says that enabling SpO2 sensing will reduce the ring’s battery life. Oura Ring Gen 3 has an estimated battery life of a week, but for the past nine months I’ve generally gotten around 4-5 days on a single charge.
In the end, it’s encouraging to see that Oura finally delivers on many of the promised Gen 3 features. (The HR tracking feature was also introduced recently, another feature that was absent at launch.) This is especially true since Oura introduced a new $6 monthly subscription for generation 3, and as you might expect, it wasn’t a popular decision among long-time customers. While the sting of having to pay the subscription won’t go away, little consolation now is that users get more than they initially promised.