Oura, Sleep Rings and Insomnia: What a Sleep Clinic Study Found

Quick Summary

• A 2025 study tested three sleep rings (Oura, SleepOn and Circul) against polysomnography, the medical gold-standard sleep test, in patients at a university sleep clinic (Herberger et al., 2025).

• Sleep ring averages looked reasonable across the group, but those averages hid large errors on individual nights. The Oura ring’s total sleep estimate was off by as much as 97 minutes for one person.

• Sleep rings were weakest at the measurements are key for insomnia: detecting time spent awake, and reporting bad nights accurately. All three rings made poor nights look better than they were.

• The researchers concluded that sleep ring numbers are not accurate enough to assess an individual person’s sleep on any single night (Herberger et al., 2025).

Are the Oura Ring and Other Sleep Rings Useful for Insomnia?

You wake up after a night of tossing and turning, feeling exhausted. You reach for your phone, open your sleep tracker app, and it greets you with a surprisingly good sleep score. Or the opposite happens: you feel fine, but your ring insists you had a terrible night. Who are you supposed to believe, your own experience or the data on your screen?

This gap between how we feel and what our trackers report is a common experience. Wearable ring trackers like the Oura Ring are a popular and convenient way to monitor sleep, and they promise a detailed look at each night’s sleep (some sleep clinics will even try to sell you one).

But most studies checking how accurate sleep rings are have tested them on healthy, mostly young volunteers who already sleep well. Those studies don’t tell us much about how the rings perform for people who have ongoing sleep problems.

So researchers at Charité University Medicine Berlin set out to fill that gap (Herberger et al., 2025). They asked 45 adults who were already attending the sleep clinic, with conditions including chronic insomnia and sleep apnoea, to wear three rings for a night:

• the Oura Ring (Generation 3)

• the SleepOn Go2Sleep and

• the Circul+ Ring

On the same night, each person had polysomnography (PSG), an overnight laboratory test that records brain waves, breathing and heart rhythm and is the clinical gold standard for measuring sleep.

Lining up each ring against the PSG recording showed where the ring was accurate and where it wasn’t.

So, are sleep rings as accurate as they market themselves to be when it comes to those with sleep disorders?

Are Oura And Similar Sleep Rings Accurate?

Herberger et al. (2025) found that sleep rings like the Oura Ring could appear accurate when results were averaged across all participants. However, this average masked substantial errors for individual users on individual nights.

In other words, a ring may perform reasonably well at the group level while providing inaccurate results for a particular person on a given night (Herberger et al., 2025).

For example, Herberger and colleages found the sleep rings to be accurate on average for total sleep time, the number of minutes a person actually spends asleep:

·      Oura ring: overestimated total sleep time by about 12 minutes on average.

·      SleepOn ring: overestimated total sleep time by about 50 minutes on average.

·      Circul ring: underestimated total sleep time by about 31 minutes on average.

Although the Oura ring’s average error of 12 minutes may appear reassuringly accurate, Herberger and colleages found individual results showed substantial variation. The Oura ring underestimated total sleep time by 54 minutes for one participant and overestimated sleep by 97.5 minutes for another. This represents a total range of approximately 2.5 hours between the largest underestimation and overestimation.

This pattern can be likened to a bathroom scale that is correct on average across a whole waiting room of people, but shows 10 kg light for one person and 7 kg heavy for the next. The average makes it look like the scale is fine. But the average tells you nothing about whether your own number is right.

The authors concluded that these individual differences were too large for ring-based sleep estimates to be used by sleep clinicians to diagnose sleep disorders (Herberger et al., 2025).

Okay. So sleep rings aren’t great for giving you an accurate reading of your night. But is that all there is to the inaccuracy?

Why Does My Sleep Ring Say I Slept Well When I Feel Awful?

Your sleep ring may say you slept well after a rough night because sleep rings are generally better at detecting sleep than identifying periods of wakefulness. In Herberger et al. (2025), the rings failed to detect approximately half of participants’ awake time, with accuracy declining further on nights with more disrupted sleep. As a result, they may overestimate sleep efficiency and make poor-quality sleep appear better than it was.

Do Oura And Other Sleep Rings Accurately Detect Time Awake During The Night?

The sleep rings, including the Oura ring, failed to detect more than half of the time participants spent awake. Although the Oura and SleepOn rings correctly identified sleep more than 90% of the time when compared with polysomnography (PSG), their accuracy was substantially lower when identifying wakefulness (Herberger et al., 2025):

·      Oura ring: correctly identified 46% of the time participants were actually awake.

·      SleepOn ring: correctly identified 37% of wake time.

·      Circul ring: correctly identified 35% of wake time.

In practical terms, if you lay awake for 60 minutes during the night, the Oura ring would on average log only about 28 of those minutes as wake. The other half hour or so would be counted as sleep, most often as light sleep (Herberger et al., 2025).

Are Sleep Rings Less Accurate on Bad Nights?

Yes. The Oura and SleepOn rings missed more wake time on nights when participants spent longer periods awake. Both devices underestimated wake after sleep onset (WASO), the total time spent awake after initially falling asleep. This underestimation of WASO increased as actual wake time increased (Herberger et al., 2025).

Put simply, the longer a person was awake during the night, the more wake time these rings failed to detect. This limitation would be especially unhelpful for people with insomnia, for whom prolonged nighttime wakefulness is often a central symptom.

So the sleep rings weren’t great with detecting time awake for sleep clinic patients. Does that mean they over-estimate how well you sleep?

Do Sleep Rings Overestimate How Well You Slept?

Yes. All three sleep rings, including the Oura ring, overestimated sleep efficiency among participants whose actual sleep efficiency was low (Herberger et al., 2025). Sleep efficiency is the percentage of time in bed spent asleep and is a key measure used to assess insomnia.

The sleep rings also made errors on time to fall asleep. The SleepOn and Circul rings underestimated time to fall asleep by about 19 and 25 minutes on average, and the Oura ring underestimated the longer times to fall asleep (Herberger et al., 2025).

The practical upshot for anyone with insomnia is that a poor night is likely to be reported as better than it was. This is particularly problematic for insomnia because, as Herberger and colleagues (2025) point out, insomnia is partly defined by more than 30 minutes of wakefulness per night on at least three nights a week. A device that misses half an hour of wakefulness could therefore miss the very thing being measured in insomnia.

Can A Sleep Ring’s Error Be Corrected?

The researchers suggested this would be difficult. Why? Because the size of each sleep ring’s error was not fixed. The error changed depending on how the person actually slept (Herberger et al., 2025).

A fixed error is somewhat easy to fix. Think of a kitchen clock that always runs 10 minutes fast. The clock is wrong, but it is wrong in the same way every time, so you can take 10 minutes off in your head and know the real time. If a sleep ring always added the same number of minutes to your sleep, you could correct it the same way.

The Oura ring and sleep rings in the Herberger study did not behave like that clock. The direction of the error was different after a good night than after a bad night. And the error was not always in the same direction.

After a poor night, all three rings made sleep look more efficient (better) than it was. But after a very good night, the Oura and Circul rings did the opposite and made sleep look less efficient than it was. The SleepOn ring overestimated sleep efficiency across the whole range (Herberger et al., 2025).

Interestingly the error problem is not limited to sleep rings: Chinoy and colleagues found a similar pattern, with errors that changed depending on how well the person slept, across seven other consumer sleep trackers (Chinoy et al., 2021).

If Sleep Rings Miss So Much Wake Time, Why Do They Score 85% Accuracy?

Sleep rings can appear accurate overall because most of the night is typically spent asleep. In Herberger et al. (2025), overall sleep–wake accuracy was 85% for the Oura Ring and 84% for the SleepOn Ring. However, these figures can be misleading: a device that classifies most periods as sleep may achieve high overall accuracy while still failing to detect a substantial amount of wake time.

That result raises the obvious question: why is being awake so hard for a sleep tracker ring to spot?

Why Do Sleep Rings Miss Time Spent Awake?

Sleep rings tend to miss time spent awake because they don’t measure sleep directly. PSG measures brain activity. A sleep ring estimates sleep from signals at the finger, such as heart rate, heart rate variability (the small beat-to-beat changes in heart rhythm), skin temperature and movement.

That indirect approach has a known blind spot. People lying still but awake tend to be scored as asleep. Wrist actigraphy, a movement-based sleep tracker used in research for decades, has long had the same problem (Paquet et al., 2007).

The wake-detection weakness is also not new, and not limited to people with sleep disorders. Across earlier sleep ring studies in healthy adults, the devices correctly detected sleep at least 89% of the time, but correctly detected wake only 18% to 54% of the time (de Zambotti et al., 2019; Roberts et al., 2020; Altini & Kinnunen, 2021; Chinoy et al., 2021; Miller et al., 2022). For more on those findings, see our guide to earlier studies of sleep trackers.

For a healthy sleeper who is awake for only a few minutes each night, missing half of that wake time is unlikely to have a meaningful effect. However, for someone with a sleep disorder, whose sleep may include prolonged periods of wakefulness, poor wake detection is a significant limitation

If the rings have trouble telling wake from sleep, what about the finer detail they report, such as deep sleep and REM?

Do The Oura Ring And Similar Sleep Ring’s Give Accurate Deep Sleep and REM Numbers?

The results of Herberger and colleagues suggest sleep staging was the Oura and other rings’ weakest area. Agreement with PSG was limited (Herberger et al., 2025):

·      Oura ring: 53% overall accuracy across the four categories (wake, light, deep, REM).

·      SleepOn ring: 50% accuracy.

·      Circul ring: 35% accuracy.

All three rings frequently classified actual wakefulness as light sleep and often misclassified deep sleep as light sleep.

REM-sleep detection varied substantially across devices. The Oura Ring correctly identified 55% of REM sleep, compared with just 14% for the Circul Ring (Herberger et al., 2025).

Deep-sleep estimates also showed a large difference between average and individual accuracy. For example, the Oura Ring’s average error for deep sleep was only 6 minutes, but individual estimates ranged from an underestimation of 211 minutes to an overestimation of 141 minutes (Herberger et al., 2025).

These sleep-stage findings are consistent with earlier studies in healthy adults and adolescents, which also found that sleep rings had limited accuracy for identifying sleep stages (de Zambotti et al., 2019; Chee et al., 2021).

The results above cover the three rings together. Does the best-known Oura Ring do any better than the lesser known sleep rings?

Is the Oura Ring More Accurate Than Other Sleep Rings?

The Oura ring had the smallest average errors when compared to the SleepOn and Circul+ Ring. However, the Oura and SleepOn rings had similar results on most measures The Circul ring performed clearly worse.

The table below summarises the main results from Herberger et al. (2025).

Measure	Oura Ring (Gen 3)	SleepOn Go2Sleep	Circul+ Ring
Total sleep time (average error)	Over by 12 min	Over by 50 min	Under by 31 min
Total sleep time (individual error range)	54 min under to 98 min over	4 min under to 146 min over	167 min under to 112 min over
Sleep/wake accuracy	85%	84%	66%
Wake correctly detected	46%	37%	35%
Sleep stage accuracy (4 stages)	53%	50%	35%

Even the better-performing rings showed limited accuracy in detecting wakefulness and identifying sleep stages—measures that are particularly important when assessing sleep problems. The authors concluded that, while sleep rings may be useful for describing sleep patterns across groups, their direct estimates are not sufficiently accurate for evaluating an individual’s sleep (Herberger et al., 2025).

Clinical Comment

If your ring’s numbers have ever seemed out of step with how you actually slept, this study offers one likely explanation. Sleep rings were weakest at detecting wakefulness and at reporting poor nights accurately, which are the features that define a night of insomnia (Herberger et al., 2025). We encourage trusting your own account of the night over the app.

You may be also wondering about more favorable claims about the Oura Ring from other scientific studies. These findings do not necessarily contradict. Two larger studies reporting higher accuracy only recruited healthy participants and excluded people with sleep disorders (Svensson et al., 2024; Robbins et al., 2024). As noted above, a ring may perform reasonably well in people with healthy, uninterrupted sleep while also performing less accurately in people with disrupted sleep.

Overall, we suggest don’t let a low score set the tone for your day, and don’t let a good score override your own feeling that you slept badly. If the two disagree, the Herberger et al. (2025) findings suggest your own experience is at least as important as the app.

And don’t let a sleep clinic sell you an Oura ring - especially if you have insomnia.

Where To From Here?

If you are dealing with ongoing sleep problems, a more advanced tracker is unlikely to be the answer. A clinical interview with a Behavioral Sleep Medicine specialist can look at your sleep pattern as a whole and work out what is causing the problem. For chronic insomnia, the recommended first-line treatment is Cognitive Behavioral Therapy for Insomnia (CBT-I), a structured programme that targets the thoughts and habits that keep poor sleep going (Edinger et al., 2021).

CBT-I works on the causes of the problem rather than the numbers on a screen. It helps you rebuild a stable sleep pattern that you can judge by how you feel during the day, not by what your sleep ring tells you.

Frequently Asked Questions About Oura, Sleep Rings And Insomnia

Q1: How accurate is the Oura ring for sleep tracking?

A1: The Oura ring’s accuracy is reasonable on average but can be well off for individual nights. A 2025 study on sleep clinic patients found that while the Oura ring’s average error for total sleep time was only 12 minutes, individual errors were much larger, ranging from underestimating sleep by 54 minutes to overestimating it by 97.5 minutes (Herberger et al., 2025). Researchers concluded these individual differences are too large for the rings’ readings to be used for clinical assessment.

Q2: Can sleep rings like Oura detect insomnia?

A2: Sleep trackers cannot reliably detect insomnia because they struggle with the very measurements that define it. A 2025 study found that three sleep rings, Oura, SleepOn and Circul, were poor at detecting time spent awake and tended to report bad nights as being better than they actually were (Herberger et al., 2025). For example, all three tested rings overestimated sleep efficiency, the percentage of time in bed actually spent asleep, for people whose real sleep efficiency was low, which is a key feature of insomnia.

Q3: How accurate is deep sleep tracking on rings like Oura?

A3:  Deep sleep tracking on rings like the Oura is generally not accurate. A 2025 study of Oura, SleepOn and Circul rings found sleep staging was the rings’ weakest area. The Oura ring showed an average deep sleep error of only 6 minutes, but individual errors ranged from underestimating by 211 minutes to overestimating by 141 minutes (Herberger et al., 2025). The rings frequently mislabelled real deep sleep as light sleep, making a single night’s deep sleep figure from a ring a rough estimate at best.

Q4: How well do sleep rings detect when you are awake?

A4: Sleep rings are poor at detecting when you are awake during the night. A 2025 study comparing Oura, SleepOn and Circul rings to the gold-standard sleep test found they were good at recognising sleep but struggled to recognise wakefulness (Herberger et al., 2025). The Oura ring, for example, correctly identified only 46% of the time participants were actually awake. This means if you were awake for an hour, the ring would on average log only about 28 of those minutes as wake.

Q5: Are sleep rings accurate for people with sleep apnoea?

A5: Sleep rings have not been shown to be accurate enough to assess an individual person’s sleep when that person has a sleep disorder. A 2025 study tested three rings, Oura, SleepOn and Circul, on sleep clinic patients with conditions including sleep apnoea and insomnia, and found that while average results sometimes looked reasonable, the errors on any single night were often large (Herberger et al., 2025). The study did not separate results by disorder, so it cannot say how the rings perform for sleep apnoea specifically.

Q6: Which sleep ring is the most accurate?

A6: The Oura and SleepOn rings performed similarly in a 2025 study, and the Circul ring performed clearly worse. The study compared the Oura Ring, SleepOn Go2Sleep and Circul+ Ring against a medical-grade sleep test, and the Oura ring had the smallest average errors for total sleep time and sleep efficiency (Herberger et al., 2025). However, even the better-performing rings showed large individual errors and struggled with detecting wakefulness and sleep stages, leading researchers to conclude they are not accurate enough for individual assessment.

Q7: Why does my sleep ring say I slept well when I feel tired?

A7: Your sleep ring may say you slept well when you feel tired because trackers tend to make poor nights look better than they were. A 2025 study found that Oura ring, Circul Ring, and SleepOn overestimated sleep efficiency for people who slept poorly and were poor at detecting time spent awake during the night (Herberger et al., 2025). A sleep ring that misses time spent awake most often logs that wake time as light sleep, so the ring’s summary of the night can look better than the night you actually had.

References

Altini, M., & Kinnunen, H. (2021). The promise of sleep: A multi-sensor approach for accurate sleep stage detection using the Oura ring. Sensors, 21(13), 4302.

Chee, N. I. Y. N., Ghorbani, S., Golkashani, H. A., Leong, R. L. F., Ong, J. L., & Chee, M. W. L. (2021). Multi-night validation of a sleep tracking ring in adolescents compared with a research actigraph and polysomnography. Nature and Science of Sleep, 13, 177–190.

Chinoy, E. D., Cuellar, J. A., Huwa, K. E., Jameson, J. T., Watson, C. H., Bessman, S. C., Hirsch, D. A., Cooper, A. D., Drummond, S. P. A., & Markwald, R. R. (2021). Performance of seven consumer sleep-tracking devices compared with polysomnography. Sleep, 44(5),

de Zambotti, M., Rosas, L., Colrain, I. M., & Baker, F. C. (2019). The sleep of the ring: Comparison of the ŌURA sleep tracker against polysomnography. Behavioral Sleep Medicine, 17(2), 124–136.

Edinger, J. D., Arnedt, J. T., Bertisch, S. M., Carney, C. E., Harrington, J. J., Lichstein, K. L., Sateia, M. J., Troxel, W. M., Zhou, E. S., Kazmi, U., Heald, J. L., & Martin, J. L. (2021). Behavioral and psychological treatments for chronic insomnia disorder in adults: An American Academy of Sleep Medicine clinical practice guideline. Journal of Clinical Sleep Medicine, 17(2), 255–262.

Herberger, S., Aurnhammer, C., Bauerfeind, S., Bothe, T., Penzel, T., & Fietze, I. (2025). Performance of wearable finger ring trackers for diagnostic sleep measurement in the clinical context. Scientific Reports, 15, 9461.

Miller, D. J., Sargent, C., & Roach, G. D. (2022). A validation of six wearable devices for estimating sleep, heart rate and heart rate variability in healthy adults. Sensors, 22(16), 6317.

Paquet, J., Kawinska, A., & Carrier, J. (2007). Wake detection capacity of actigraphy during sleep. Sleep, 30(10), 1362–1369.

Roberts, D. M., Schade, M. M., Mathew, G. M., Gartenberg, D., & Buxton, O. M. (2020). Detecting sleep using heart rate and motion data from multisensor consumer-grade wearables, relative to wrist actigraphy and polysomnography. Sleep, 43(7), zsaa045.

Robbins, R., Weaver, M. D., Sullivan, J. P., Quan, S. F., Gilmore, K., Shaw, S., Benz, A., Qadri, S., Barger, L. K., Czeisler, C. A., & Duffy, J. F. (2024). Accuracy of three commercial wearable devices for sleep tracking in healthy adults. Sensors, 24(20), 6532.

Svensson, T., Madhawa, K., Nt, H., Chung, U., & Svensson, A. K. (2024). Validity and reliability of the Oura Ring Generation 3 (Gen3) with Oura sleep staging algorithm 2.0 (OSSA 2.0) when compared to multi-night ambulatory polysomnography: A validation study of 96 participants and 421,045 epochs. Sleep Medicine, 115, 251–263.

Written By Dan Ford, DBSM, Sleep Psychologist

Published By The Better Sleep Clinic