What Does Your Oura Ring Track & Can You Even Trust It?

A lot of times, I am scrolling through Instagram, finding content creators showing off their Readiness and Sleep Scores. When I wasn’t an Oura user, I also used to wonder what exactly goes behind these numbers, what exactly the Oura ring tracks, and on what basis it is giving these numbers.

Now, being an Oura user for months, I think I have a pretty good idea and know the Oura ring in and out. I can say for sure you shouldn’t believe everything you see, but how will you know what data is true and what is absolute BS?

I have clearly laid out what metrics the Oura ring tracks and what data it purely estimates based on what it tracks. I hope it helps you decode the ring a bit.

At a glance

The shortlist10 picks, tap one to jump to it.

1. 01Heart Rate Tracking
2. 02Tracking Body Temperature
3. 03SpO2 Tracking
4. 04Movement
5. 05Respiratory Rate
6. 01Sleep
7. 02Daytime Stress
8. 03Menstrual Cycles

Metrics That Oura Ring Actually Tracks#

I was really curious to understand how Oura does all that it does. My curiosity led me to something called “biosignals”. So, I got to know that behind the scenes, Oura tracks parameters, also known as biosignals, from the human body using advanced sensors and in-built technology. Based on this, it further draws in-depth insights.

Oura Gen3’s Sensors:

1. PPG (Photoplethysmography) Sensors
2. NTC (Negative Temperature Coefficient) Sensors
3. 3D Accelerometer
4. Infrared LED
5. Red LEDs
6. Green LEDs

01Heart Rate Tracking#

Oura tracks your Heart Rate, Heart Rate Variability, and much more during both day and night through its PPG sensors. It doesn’t just simply give you the beats per minute; you can do spot checks at any time and see how it’s reflected in your stress levels, more on that later.

Whenever Oura is measuring your heart rate, you will see a green LED light coming from the sensors. Oura doesn’t track your heart rate continuously; it does so every 5 minutes whenever you’re wearing the ring.

Along with measuring your HR and HRV during the day, it does so even when you are sleeping. You will also see metrics like lowest HR, resting HR, and trends in all these HR metrics in the app.

For even more holistic heart monitoring, Oura allows you to track and record your heart rate live during your workouts with a feature called “Record Workout HR.”

02Tracking Body Temperature#

Oura Ring detects any changes in your body temperature with its negative temperature coefficient (NTC) sensors. It measures the temperature of your skin directly from your finger, which helps it understand all the changes happening in your body.

Moreover, while Oura clearly states that it measures your body temperature at all times, it does not show us the same on the app. We can only see one temperature measurement for each day, and over a period of time, a graph will be ready for us.

As shown in the picture, Oura doesn’t give your body temperature in Fahrenheit. Instead, it will give you a temperature change in degrees Celsius from your baseline temperature. For example, it gives me -0.1°C, but it won’t tell me the exact temperature.

While this is helpful as well, last week I was actually down with a fever of 100°F in the night. But since the app doesn’t tell body temperature as frequently as other metrics. It only showed me the temperature it captured once in the day, and at that point of the day, I wasn’t having a fever.

If Oura so clearly states that the ring tracks the temperature all the time, why doesn’t it show me the same?

03SpO2 Tracking#

Oura tracks SpO2, i.e., peripheral oxygen saturation, with its red LED sensor and gives a more accurate assessment of your breathing regularity. While you are sleeping, light is sent to your finger from the ring’s red and infrared LEDs.

This process helps in understanding the level of SpO2 in your blood, as highly oxygen-saturated blood reflects more red light compared to infrared light. It also suspects breathing disturbances in your sleep. SpO2 is tracked only when we are sleeping, and the data can be seen only after a sleep of at least 3 hours.

Make no mistake, yesterday I actually took a super short nap during the day, and when I woke up, I saw the red light on my finger. That means the SpO2 sensor was working, but since it only shows SpO2 for sleep times greater than 3 hours, I did not see any data for the SpO2 recorded. Too bad!

04Movement#

Oura ring proactively tracks your daily steps, distance traveled, and calories burned 24/7 with the help of a highly sensitive 3D accelerometer. The Oura app provides personalized recommendations based on your activity level to help you optimize your physical activity. I also learned that Oura ensures that you get credit every time you move.

Not just this, it also designs an Activity Goal, especially for you, and keeps track of your progress, activity levels, and calories burned every day. Oura offers AAD, which is Automatic Activity Detection for over 40 different kinds of activities, which I personally think is very cool.

Note: Additionally, you can turn on the location services option on the Oura app, which will help Oura track your workout routes.

05Respiratory Rate#

Oura closely monitors your breathing patterns with the help of its Infrared Photoplethysmography sensors (PPG). It gives a detailed analysis of the number of breaths you take per minute.

Oura also renders a detailed report of any irregularities in breathing during your sleep cycles that would indicate disturbance in sleep. Irregularities in respiratory rate can also cause changes in health; for instance, an elevated respiratory rate could be a sign of stress, fever, or illness, while a lower rate might indicate deep, restful sleep.

Oura’s Estimations Based on Tracked Data#

Now, there’s certain data that, no matter how accurate, isn’t actually measured or tracked by the ring. The Oura ring tracks fluctuations in blood from the finger and gives you your heart rate metrics. However, other metrics are mere estimations, and I think the users should clearly differentiate between the two.

I am not saying that the data mentioned below, given by the Oura app, isn’t accurate; all I am saying is that it is not exactly tracked and should not be relied upon clinically. There’s a difference between medically graded and non-medically graded data, and you should know that well before looking at any numbers an app throws at you.

01Sleep#

Oura monitors your sleep stages and gives you a detailed analysis of your total sleep time, sleep efficiency, any disturbances in sleep, etc. It uses your heart rate patterns, body temperature, respiratory rate, and body movement to provide you with a personalized sleep score between 0 and 100.

Behind the scenes, Oura, at the end of the night, collects all your measured data, and the data is then bifurcated into sleep intervals of 5 minutes each. This data is then further classified into sleep stages, such as awake, light, deep, and REM. By this classification, you can have a fair understanding of how your sleep was.

Every morning, Oura gives you a detailed sleep analysis, which tells you how your last night’s sleep was and if you need to meditate, rest, or take a short nap.

02Daytime Stress#

Daytime Stress is the physiological stress estimated by Oura. Oura ring’s Daytime Stress tracking feature constantly tracks your temperature, motion, heart rate, and heart rate variability (HRV) throughout the day to provide you with personalized insights about your daytime stress levels.

Although Oura rings’ sensors gather data in real-time, the Daytime Stress chart updates every 15 minutes.

03Menstrual Cycles#

Oura comes with a feature called Cycle Insights to help you predict and monitor your period. Hormonal changes lead to changes in body temperature, which affect the menstrual cycle. You do have to log your periods for at least 3 months for Oura to give you accurate predictions.

Oura uses a combination of your night body temperature and HRV to predict your next period date. Due to variations in hormonal levels, there are variations in body temperature during the menstrual cycle.

Oura takes a minimum of 60 days initially to collect the required data and establish a baseline body temperature for you. This then helps you see and understand your cycle phases clearly.

04VO2 Max#

Oura clearly states that it estimates your body’s Cardio Capacity or VO2 max. It is basically the maximum oxygen your body utilizes during exercise or workouts. It tells you what climbing 3 floors of stairs will look like for you. Again, all of it is simply a guess by the app, and that’s exactly why you shouldn’t take it seriously.

05Cardiovascular Age#

Oura can now also predict your Cardiovascular age. In case you are wondering what that is, it is the estimated age of your heart and blood vessels, which is different from your chronological age. By closely understanding your heart rate patterns and gauging your lifestyle, it can predict your cardiovascular age.

It estimates Cardiovascular age with Pulse Wave Velocity. Oura then, with the help of your sex, age, and height, constructs a wave pattern that tells us about arterial stiffness. It measures your unique wave shape during sleep and estimates your arterial thickness, which is your cardiovascular age.

Frequently Asked Questions#

Wrap Up#

Overall, the Oura ring is a powerful little tool that empowers its users to have personalized insights into their bodies and minds. It helps users make informed choices and guides them towards a fulfilled lifestyle.

As I have already said above, be very sure what numbers and data you want to believe in and what data you don’t want to believe in, because there’s absolutely no ring/watch or wearable that gives you all the accurate information. That’s why it is important to do your own research. 

I think Oura is doing a good job in tracking most of the metrics. It’s the Stress, VO2, and Cardiovascular Age features that are a turn-off for me. I get they are trying to be.

If you want to explore more about Oura Ring features and data insights, you may also want to check How to Share Oura Data With Doctor? It’s Super Easy! and How Does Oura Ring Track Your Sleep?