- Oura Ring Review
- Oura Ring vs. WHOOP – What’s The Better Choice?
- Frequently Asked Questions
- My Take On This Smart Ring After 30 Days of Use
After publishing my in-depth review of the WHOOP Strap, several readers kept asking me if I could try the Oura Ring and do a full comparison. So I finally pulled the trigger and ordered an Oura Ring, which I’ve been wearing for the past couple of weeks.
In this review, I’ll tell you everything I’ve learned about this wearable health tracker and how it compares to the WHOOP band I’ve had for over 1.5 years.
Oura Ring 2
Oura Ring Review
- Slick and futuristic design
- Comfortable to wear
- Long battery life and data retention
- Accurate HR tracking
- Almost instantaneous data transfer from ring to mobile app
- Integration with Apple Health and Google Fit
- Sleep tracking is not always 100% accurate
- Readiness score isn’t super helpful
The Oura Ring is a futuristic-looking wearable that packs a ton of advanced sensors into an incredibly small form factor. In fact, even after having worn my Oura Ring for several weeks, I’m still amazed at how such a small ring can house so much technology. It’s simply a marvel of engineering!
The goal of the Oura Ring is to make health and wellness information personal and accessible. That makes the Oura Ring more comparable to the WHOOP 3.0 strap than to traditional activity trackers like the FitBit and Apple Watch.
In a nutshell, the Oura Ring can track the following metrics:
- Heart rate (HR) and heart rate variability (HRV)
- Body temperature
- Respiratory rate (breathing rate)
- Active calorie burn
- Steps and activity score
- Total sleep, sleep efficiency, sleep quality and stages of sleep
- Readiness score (akin to WHOOP’s recovery score)
Heart Rate and Heart Rate Variability
The ability to accurately track your heart rate is crucial because it’s an important factor for activity and sleep tracking, as well as for calculating your readiness score.
Arguably more important than your (resting/sleeping) heart rate is your heart rate variability, which is the difference in timing between heartbeats. As I explained in my review of WHOOP (see blog post and YouTube video), HRV is a reliable indicator of how your autonomic nervous system is doing.
A low HRV (compared to your baseline) is a sign that the sympathetic nervous system — the branch responsible for the fight or flight response (among other things) — is in overdrive. That’s usually an indication that your body is using its resources to recover from strain or stress, or to fight disease.
Sudden changes in body temperature while sleeping can also be an indicator that your body might be coming down with something. That’s why Oura Ring keeps tabs on your temperature at night and warns you if it deviates from your baseline.
The rate at which you breathe is relatively consistent, as I explained in my review of the Eight Sleep system. A sudden spike in breathing rate can be an indication that you ate too much too late, or of a respiratory infection like COVID-19.
Active Calorie Burn
While knowing how many calories you’ve burned during the day can be useful, you should recognize that none of the wearables I’ve tested — including the Oura Ring, WHOOP strap, Biostrap and Apple Watch — are incredibly accurate in this regard.
That’s because you can only accurately track your active calorie burn if you know your basal metabolic rate (BMR) — the calories your body burns without any physical activity involved.
To get accurate calorie tracking data, you have to perform a special (BMR) test and then feed the results to your wearable. None of the devices mentioned above allow you to define your BMR, but WHOOP is apparently working on that, together with PNOE.
The bottom line is that you shouldn’t get too hung up on activity tracking, regardless of what fitness tracker you’re using.
Steps taken is another metric of questionable value. Personally, I don’t care much about it because it doesn’t influence my behavior. I do CrossFit five to six times a week, regardless of how many steps I’ve taken on a given day.
However, I appreciate that for some people, seeing how many steps they’ve taken at midday might be a motivating factor to go for a walk in the afternoon (for example) — especially for those who don’t have a regular fitness routine.
Sleep and Stages of Sleep
Sleep tracking is arguably the most important feature of Oura Ring. In a nutshell, the Oura Ring can track the following sleep-related metrics:
- Total sleep: How much time you spend in all stages of sleep combined (light, deep, REM, awake).
- Efficiency: How much time you spend asleep after going to bed.
- Restfulness: Sleep disturbances by wake-ups and restless time (tossing and turning).
- REM sleep: An active but mentally restorative phase of sleep during which most dreams occur.
- Deep sleep: The physically-restorative phase of sleep.
- Latency: How long it took you to fall asleep.
- Timing: Consistent sleep and wake times are important for your circadian rhythm.
Of course, sleep tracking has to be accurate to be of value, and we’ll talk about how accurate Oura Ring is in comparison to WHOOP and Eight Sleep later in the article.
Oura Ring’s Readiness score is akin to WHOOP’s recovery score. It’s supposed to give you an idea of how prepared your body is for taking on strain, both physically and mentally.
The factors that Oura Ring takes into account to calculate your daily readiness score include:
- Sleeping heart rate.
- HRV balance.
- Body temperature.
- Recovery index (how long it took for your resting heart rate to stabilize during the night).
- Sleep score from the previous night.
- Sleep balance (a comparison of your sleep needs vs. the actual sleep you’ve gotten over the past two weeks).
- Previous day activity.
- Activity balance.
Overall, I consider the readiness score useful but not as insightful as the recovery score I get from WHOOP every morning.
Form Factor: Ring vs. Wrist Strap
One of the most striking differences between the Oura Ring and other health trackers is its form factor. While you have to wear most devices in this category around your wrist, the Oura Ring is, as the name implies, a ring.
That certainly makes Oura stand out and gives the device an extra cool factor. However, there are also practical implications stemming from this design decision.
For example, many wrist-worn devices have trouble accurately monitoring your heart rate during physical activities that involve wrist movements. CrossFit and boxing are two examples of exercise routines that make it difficult for devices like the Apple Watch, Biostrap or WHOOP to reliably capture heart rate data.
Wrist movement doesn’t negatively impact the Oura Ring at all. Plus, many people may find wearing a ring more comfortable than wearing a wrist strap.
Additionally, the Oura Ring has two heart rate sensors on each side of the ring to increase its chances of capturing good data and reducing noise. Most wrist-worn devices have sensors that are physically right next to each other. That can lead to a higher noise-to-signal ratio, and thus to less reliable HR data.
Unfortunately, Oura’s form factor also has some disadvantages.
For example, Oura doesn’t recommend wearing the ring during workouts that involve a barbell, dumbbell or kettlebell because those activities would scratch the device. As a result, I always take off my Oura Ring before each CrossFit class.
For me, that’s only a minor inconvenience because I don’t care much about activity tracking and Oura’s mobile app can automatically import the workout data captured by my Apple Watch.
The real problem is that I sometimes forget to leave my Oura Ring at home before leaving for the gym. That increases my chances of misplacing the ring in the car or gym. When I leave the ring in the car, I almost always forget to put it back on. That leads to gaps in my normal activity data, which could influence my next day’s readiness score.
As I was writing this section of the blog post, I realized that I left my Oura Ring on the charger in my office. I put it there before I left for my workout this morning and then forgot to put it back on.
The second and even bigger issue with a ring is the fit. My WHOOP strap comes with an elastic strap that I can infinitely adjust to achieve a perfect fit. The Oura Ring is made from metal and can’t be adjusted.
When I ordered my Oura Ring, I first got a sizing kit in the mail to help identify what size ring I needed. The problem is that the diameter of my fingers changes throughout the day and night.
Plus, I had to take the size of my knuckles into account when selecting the proper ring size. My knuckles are naturally thicker than the rest of my fingers. As a result, the smallest ring that fits over the knuckle of my finger is still a bit loose.
That’s a problem because if the heart rate sensor isn’t in close contact with the skin, the resulting heart rate data will be inaccurate. That might explain some of the (what I’d consider inaccurate) sleep data I’ve been getting.
The imperfect fit issue is exacerbated by the fact that Oura uses red LEDs for its HR sensor. As I explained in my comparison of Biostrap and WHOOP, red LEDs have some advantages but they’re also more susceptible to noise from ambient light or an improper fit.
The Oura Ring packs a variety of biometric sensors into a tiny form factor. Specifically, the inner side of the ring includes the following sensors:
- Optical heart rate sensor (pulse oximeter) using red LEDs
- NTC (negative thermal coefficient) body temperature sensor
- 3D accelerometer and gyroscope
The Oura Ring uses two infrared photoplethysmography (PPG) sensors that are located on either side of the lower half of the ring and that take HR measurements 250 times per second.
Infrared light (as opposed to green light) can penetrate the skin deeper and take readings from blood vessels that are located deeper inside the tissue. The downside to infrared-based sensors is that they’re more prone to sensor noise caused by motion and ambient light.
My take on this is that while infrared PPG sensors aren’t perfect in all conditions, if your Oura Ring fits tightly around your finger, it shouldn’t negatively impact the signal the sensors receive.
Plus, the Oura Ring has two sensors, allowing the device to use the data from the sensor with the better signal.
Overall, I like the form factor of the Oura Ring and I think it’ll work fine for many people. Personally, I prefer a wrist strap that has less potential of getting in the way during CrossFit workouts.
Accuracy (of Sleep Tracking)
For a health and fitness tracker to be more than a gimmick it has to produce accurate and actionable data.
As far as exercise and calorie tracking is concerned, I have no opinion on Oura Ring’s accuracy because I never paid much attention to the data and I never wore it during a workout. As a result, most of the activity reporting I see in the Oura app stems from the workout data recorded by my Apple Watch.
As far as sleep tracking is concerned, my experience with Oura Ring has been a mixed bag. Sometimes Oura’s sleep analysis was similar to what I got from WHOOP and Eight Sleep, but other times it was completely off.
The problem is that neither of these three technologies is 100% accurate and I don’t have comparison data from a sleep lab to know with certainty which gadget is right. However, I do have some anecdotal evidence to suggest that when Oura showed different results, it was wrong and WHOOP and Eight Sleep were right.
Let me give you a few examples before we look at the limited number of scientific studies that compared the Oura Ring (and WHOOP) to polysomnography (PSG) — a sleep study that relies on an electroencephalogram (EEG).
On one of the first nights of wearing the Oura Ring, I performed a test that I usually do with all sleep trackers: I lie down in bed for about 20 minutes to see if my lack of movement and low heart rate will trick the device into thinking that I’m sleeping.
In the case of the Oura Ring, it did.
Oura Ring recorded most of those 20 minutes as light sleep. With WHOOP, that never happened. I think that’s because WHOOP has an additional sensor that measures electrodermal activity, which is a metric that changes as you fall asleep.
On another occasion, I woke up in the middle (or at the end) of a vivid dream. Humans usually (but not always) dream during REM sleep, which is a mentally active phase of sleep. The next morning I looked at the Oura Ring and it recorded the time around my awakening as light sleep.
On the other hand, WHOOP showed REM sleep right before I woke up.
Over the past four weeks, I tried wearing the Oura Ring on different fingers on both my dominant and non-dominant hand. And based on the data I’m seeing, it doesn’t appear to make much of a difference or impact the device’s accuracy in any meaningful way.
Now that we have my pseudo-scientific observations out of the way, let’s see what scientific studies have to say about the accuracy of the Oura Ring.
What Current Research Says About Oura Ring
Unfortunately, I have only found a single study, from 2017, that compared the Oura Ring with EEG-based sleep trackers. The goal of the study was to determine how accurate Oura could detect deep (PSG N3), light (PSG N1+N2) and rapid-eye-movement (REM) sleep.
The study’s authors concluded:
Summary variables for sleep onset latency (SOL), total sleep time (TST), and wake after sleep onset (WASO) were not different between ŌURA ring and PSG. PSG-ŌURA discrepancies for WASO were greater in participants with more PSG-defined WASO (p < .001). Compared with PSG, ŌURA ring underestimated PSG N3 (~20 min) and overestimated PSG REM (~17 min; p < .05). PSG-ŌURA differences for TST and WASO lay within the ≤ 30 min a-priori-set clinically satisfactory ranges for 87.8% and 85.4% of the sample, respectively. From EBE analysis, ŌURA ring had a 96% sensitivity to detect sleep, and agreement of 65%, 51%, and 61%, in detecting “light sleep” (N1), “deep sleep” (N2 + N3), and REM sleep, respectively. Specificity in detecting wake was 48%.
What that means is that the Oura Ring is relatively good at detecting sleep but not very good at detecting if you’re awake.
The accuracy for detecting when certain sleep cycles (light, deep, REM) occur is somewhat of a mixed bag, but when Oura detects the sleep stage correctly, it tends to underestimate deep and overestimate REM sleep.
How does that compare to WHOOP?
According to a randomized cross-over trial from 2020, WHOOP was accurate in detecting sleep duration (with a precision of 17.8 minutes). That study also reported highly accurate detection of REM and slow-wave (deep) sleep.
My take on this is that Oura is somewhat less accurate than WHOOP, as proven by the few studies that I’ve found and my personal experience with both wearables.
Readiness vs. Recovery Score
Besides sleep tracking, the second functionality I look for in a health tracking wearable is the ability to correlate my behavior with sleep performance and recovery.
In other words, I want to know how my lifestyle choices impact the quality of my sleep and my readiness to perform (both mentally and physically).
The metric the Oura Ring uses for that is called Readiness, which is displayed as a score from 0 to 100.
I already talked about the factors that go into this score above, so I won’t repeat them here. Instead, I’d like to talk about the usefulness of this score and compare it to the recovery score that WHOOP provides.
One thing I noticed immediately was that Oura doesn’t use visual cues to indicate your readiness (like WHOOP does). In other words, Oura relies on numerals (0-100) and a written indicator of how to interpret that score.
- Above 85 is an optimal score.
- Between 70 and 84 is a good score.
- If your readiness is below 70, you should pay attention.
While there’s nothing wrong with this method of presentation, I find WHOOP’s approach much more impactful and visually appealing.
When I open the WHOOP app every morning, I see either a red, yellow or green score. That immediately tells me where I’m at, even without looking at the details (such as my actual recovery score or the factors that contributed to it).
The problem with Oura’s approach is not that I think it’s less accurate in terms of reflecting how recovered I am, it’s that the device’s representation of that data is just much less impactful.
For example, I can tell you from the top of my head how many “red” days I’ve had this week (as reported by WHOOP) but I don’t recall a single readiness score from Oura.
I’m part of various WHOOP teams who I share my strain, recovery and sleep performance with, and we often talk about our data — especially if someone is in the red while another member is in the green (or vice versa).
I can’t see that type of “Dude, you’re in the red. What happened?” conversation stemming from Oura’s relatively bland readiness score implementation.
Oura Tags vs. WHOOP Journal
Besides knowing how “ready” I am each day, and how much I might be able to push it during workouts, Oura also offers a concept called tags.
In other words, I can tag my day with certain lifestyle behaviors or other factors that I can then correlate with changes in my sleep performance or readiness.
For example, I could tag a given day with alcohol, CBD, flu or any other of the numerous tags the Oura app offers, and those tags would then show up on my daily report. The problem is that I have to manually correlate those tags with the rest of the data the Oura Ring captured.
While that allows me to keep an eye out for trends (e.g., more deep sleep after CBD oil use), I’d rather have the Oura app automatically keep tabs on those correlations, much like the WHOOP app does via the WHOOP Journal.
The latter allows me to complete a brief questionnaire every morning (with predefined questions I want to answer). Every 30 days, I get a detailed report (see example here) that shows how each of my behaviors correlated with my HRV trend, recovery score, sleep performance and more.
In other words, Oura’s implementation of tags is a good start and a step in the right direction, but it’s nowhere near as sophisticated as the WHOOP Journal.
The issue I have with both implementations is that neither supports custom tags. So if I want to correlate the use of a certain supplement that neither platform has in its “dictionary,” I have to track that outside of the app.
The tiny battery that’s built into the Oura Ring lasts between four and seven days. Mine usually lasts close to seven days before I have to recharge the device.
Overall, Oura’s battery life is comparable to WHOOP, which lasts about five days. The “problem” with the Oura Ring is that you have to take it off your finger and place it on a charger that only works with rings of the same size as the one it came with.
For example, I have a #9 Oura Ring, so my charger only works with other #9 rings. If my wife had an Oura Ring, she wouldn’t be able to charge hers using my charger because her ring size is smaller.
That’s not a huge problem, but you won’t be able to share chargers while traveling if you and your partner have different ring sizes.
What’s a slightly bigger problem is the fact that I have to take the ring off my finger for charging. I often forget to put it back on, so removing it increases the risk for significant gaps in my data.
In comparison, I can charge my WHOOP strap without having to remove it from my wrist by using a slide-on battery pack that I can charge separately.
Data Retention and Offline Mode
What I really like about the Oura Ring is that it can store up to six weeks’ worth of data without being connected to your phone. While I don’t think I’ll ever be away from my iPhone for that long, it’s good to know that I don’t have to worry about losing data if I am.
The other thing that’s cool about Oura is the ability to switch the ring into airplane mode. Practically, that turns off the device’s Bluetooth radio, thus reducing EMF radiation while sleeping.
The only downside is that you can’t turn off airplane mode without placing the ring on its charger. You’ll have to decide if that’s worth the hassle.
In comparison, WHOOP doesn’t support offline mode and it can only retain a couple of days’ worth of data without being connected to the phone.
One feature that I have come to really appreciate is the ring’s integration with Apple Health.
By integrating with HealthKit, the Oura app can store sleep data in, and import workout data from, the Health app.
That helps me maintain a single database with all my health information. It also means that Oura can take my CrossFit workouts (which I capture using my Apple Watch) into account when calculating my next day’s readiness score.
That’s particularly helpful because I can’t wear the Oura Ring for those workouts.
In comparison, WHOOP does not support Apple Health (despite my frequent requests for it).
Pricing: One-Time Payment vs. Subscription
The Oura Ring starts at $299 for the Heritage edition, but it’s also available in a Heritage – Stealth (matte) and Heritage – Gold edition for $399. The latter two feature a different finish (color) that some users might find more fashionable.
The good news is that the regular (Heritage) edition is available in black (the one I got) and silver, so you can pick the one you like best.
What’s appealing to some users is that Oura doesn’t charge a monthly subscription fee. You only have to pay for the hardware (the ring) upfront — at least until Oura releases a new version of the ring, at which time you have to decide if you want to upgrade.
In comparison, WHOOP follows a subscription-based pricing model that costs you anywhere from $18 to $30 a month*, depending on how long you decide to commit.
There are pros and cons to each approach and your individual circumstances will determine what pricing model works best for you.
If you want to give the Oura Ring a try, you can use the link below and get redirected to ouraring.com.
Oura Ring vs. WHOOP – What’s The Better Choice?
I haven’t had my Oura Ring nearly as long as I’ve had my WHOOP strap, but I have made the decision to return the Oura Ring and continue using WHOOP.
Frankly, my intention was never to replace my WHOOP band with the Oura Ring, but I really wanted to love the device and use it in combination with WHOOP.
The Oura Ring is cool and I really like the fact that it’s a ring that can replace my regular wedding band. In fact, it looks much better than my wedding ring, and knowing that it’s packed with technology makes it just that much cooler.
I also really like some of the biometrics the ring collects (such as body temperature) and its integration with HealthKit.
In a nutshell, there’s a lot to like about the Oura Ring.
However, I’m not pleased with the sleep tracking and Oura’s implementation of its recovery index. The former appears to be inaccurate — perhaps influenced by a less-than-perfect fit of my ring — and the latter doesn’t provide the same level of visual cues and actionable data that I’m used to from WHOOP.
As a result, I can’t justify the $300 price tag and I’ll be returning my Oura Ring in the next few days.
However, once Oura releases its next-generation hardware (the new Oura Ring 3), I’ll try it again and update this review.
Frequently Asked Questions
Based on the scientific studies I’ve read and my personal experience, I think the Oura Ring can be accurate enough, depending on your use cases and the ring’s fit.
If you’re interested in learning how long you sleep or how restful your sleep is, a tight-fitting Oura Ring can give you that information.
However, if you’re interested in accurately tracking the stages of your sleep, the Oura Ring might not be the perfect choice.
Based on my experience, the Oura Ring appears to be underreporting both deep and REM sleep, compared to WHOOP.
In other words, the Oura Ring reports that I spend significantly less time in those restorative stages of sleep than I should.
Based on how I feel when I wake up, and my energy levels during the day, I don’t trust the data I’ve been getting from the Oura Ring on most days.
While Oura’s readiness index is useful, I feel it’s less impactful than WHOOP’s “traffic light” system of red, yellow and green.
More importantly, Oura doesn’t correlate lifestyle choices (tags) with sleep performance or readiness.
While I appreciate that correlation isn’t the same as causation, WHOOP’s ability to correlate behaviors (e.g., alcohol consumption) with sleep performance and recovery makes tweaking those behaviors and trying to improve one’s performance a fun exercise.
Unfortunately, no. You can only charge your Oura Ring with the charger it came with (or with another one that matches your ring’s size).
Yes, you should wear your Oura Ring during workouts because physical activity (strain) might influence your sleep needs and next day’s readiness score.
However, you should only do that for types of exercises that don’t involve pull-up bars, barbells, dumbbells or kettlebells, because they might scratch your ring.
That’s the primary reason why I haven’t worn my Oura Ring during CrossFit workouts.
While the Oura Ring isn’t a medical device meant to diagnose any serious health conditions, I believe (and studies confirm) that a sudden change in respiratory rate, HRV and sleeping heart rate can be an indication of an underlying issue. Maybe that’s why more people are interested in fitness tracking during the 2020 pandemic.
The Oura app shows my morning report almost instantaneously, and frankly much faster than the WHOOP app, which usually takes minutes to crunch the data through its algorithm. So I really like the “real-time” reporting of Oura.
While Oura does offer a feature that enables you to share your data with another person, I don’t think that you can share it with just anyone.
The Oura team suggests that you can only do this with coaches, trainers, doctors and researchers, and you have to open a support ticket to enable sharing.
In comparison, WHOOP allows you to create your own teams using the app or to join existing teams that you can share your data with.
My Take On This Smart Ring After 30 Days of Use
As I mentioned above, I really like the concept of the Oura Ring. It’s a marvel of technology. Unfortunately, it has not been as accurate in my testing as WHOOP, making the device an incredibly cool gadget that, for me, is not worth the $300 price tag.
So if you ask me whether or not you should get an Oura Ring, I’d say to give it a try and see how it works for you. However, I’d also recommend getting another fitness tracker for comparison (such as the WHOOP*) to see which one provides more helpful data based on your specific use cases. Both gadgets have a 30-day return policy, so you can always return them if you’re not happy with their performance.
If I didn’t have WHOOP or Eight Sleep to compare sleep tracking data, I’d be more inclined to incorrectly conclude that I sleep poorly most nights — despite how I feel in the mornings.
Overall, I think that the Oura Ring has potential. Perhaps in the next version, they’ll include an electrodermal activity sensor to bring the device’s sleep tracking capabilities up to par with WHOOP. I’m keeping an eye out for that and will do another review whenever the Oura Ring 3 is released.
Until then, I’d like to hear from you. How has your experience with the Oura Ring been, and have you compared it side-by-side with other fitness trackers? If so, let me know in the comments!