Oura Ring 2018 – Smart Ring Wearable Review – GadFit Singapore

August 30, 2018

The new Oura ring is quantum leaps ahead of the first generation ring by the same name. For starters, the company reduced the physical size of their smart ring to something more sensibly palatable. Personally, I’m impressed how much tech Oura managed to cramp into their new ring considering the physical “downsizing”. That being said, the new Oura ring is less conspicuous than its predecessor but still conspicuous nevertheless.

Oura claims that their smart ring is the world’s most advanced wearable for restorative sleep. After a few weeks of usage in sunny Singapore, here’s what I have to say about the Oura ring.


new vs old oura ring

It is remarkable when you look at the size of the original ring versus the new Oura ring and then you consider the sheer difference in power.

During sleep, the ring measures body temperature, and heart rate along with HRV are being sampled at 250Hz with the on board infrared optical pulse sensor. And the best part is I don’t have to worry about the ring running out of memory as the wearable stores up to 6 weeks of data before syncing. Despite the embedded tech on the interior of the ring, it wears comfortably. Impressive so far yes?

Interior of the Oura ring

Those of you wearing wedding bands might have issues pulling off the two-rings look on a regular basis. There’s only so much real estate on your hand and frankly less is more. And chances are you probably don’t want the rings side by side to prevent unnecessary wear and scratches. So that leaves you only the digit finger or you’ll have to wear the ring on  the other hand.

Point to note, most of Oura’s press images feature hand models wearing one ring only.

It was only in everyday wear that I realised the shank of the Oura ring is a tad thicker than that of a regular ring. The awareness of the ring was most stark during weights training; I can feel the Oura ring pressed against the dumbbells and barbells.

Part of this issue arose because you need to size the Oura ring so that it is snug yet easy to remove for regular charging.  (The company does deliver a beautiful sizing kit for you to choose your ring size properly before confirmation of order)

After a few weeks, I spotted mild scratches on the ring; inevitable given my active lifestyle.

Oura Ring main feature

I was able to wear the ring for all my sporting activities including running in humid Singapore, drenched in perspiration, to multiple swim sessions in a lap pool. Clearly, the ring was built to last through activities of daily living.

oura ring sleep tracking mobile app grab

According to Oura, a single charge of the ring provides up to full week of use; I managed 6 good days. The ring was definitely able to stretch to a 7th day but when battery level is low, sleep stage recording is turned off and the user is  left only with sleep duration records.

oura ring in charging dock

Charging is done via a wireless charging dock. Place the ring on the dock and a pulsating light indicates charging in progress.

I particularly like how the ring just works quietly in the background. No blinking lights nor vibrations, you just put it on after a full charge and it gets right to work. You can get an indication of the battery levels via the mobile app.

The ring featured in this review is the Heritage Black version. The matt version of the ring might be a more subdued option at $100 USD more than the standard version. Those of you looking to bling up can opt for the Balance diamond Oura ring ($999 USD) that comes encrusted with a row of five 0.005 ct diamonds.

Due to the fact that I funded the first generation ring on Kickstarter, I was given the option to purchase the new Oura ring at a huge discount this time round which I took up.


The Oura Ring records a lot of information for the user if one is committed to wearing it religiously. I’m lifting the list of stats directly from Oura’s website though I have to stress that I didn’t get any pulse amplitude variation readings; that might have been used to compute other measurements.

  • Interbeat interval (IBI)
  • Pulse amplitude variation (related to blood pressure variation)
  • ECG level resting heart rate (RHR)
  • Heart rate variability (HRV)
  • Respiratory rate
  • Movements, intensity of physical activity
  • Body temperature deviation

All the tracked stats can be accessed via the Oura mobile app.

oura ring activity mobile app grab

The company categorises the tracked metrics into three broad segments – Sleep, activity, readiness. Each category will have its own list of metrics. For example, you’d find steps, walking equivalent, hourly movement targets and so on under “Activity.”

oura ring steps versus total sleep

The tracked stats are presented in a manner similar to what any run-of-the-mill wearable company dishes out. Users can zoom in on a day or explore trends related to any of the 3 broad categories from a weekly or monthly perspective.

Also, the Oura ring mobile app writes sleep data to Apple Health but not steps. I found this strange since the ring actually does a pretty decent job tracking daily activity from the fingers.

oura ring platform 1

There’s also an Oura web platform which users can access. It allows you to overlap various tracked stats for further analysis, on top of what the mobile app is capable of.

Oura ring web platform

If you’re really serious about sleep trends and what affects your rest quality, you’d get your fix from the Oura ring web platform.


A quick search online throws up a few user reviews , mine included, that all point towards the most recent study Oura has done. This particular study was independently validated by Stanford Research Institute and you can access the summary here. After reading it, I’m lifting a paragraph that in my opinion is of utmost importance:

“Multisensor sleep trackers, such as the ŌURA ring have the potential for detecting outcomes beyond binary sleep–wake using sources of information in addition to motion. While these first results could be viewed as promising, future development and validation are needed.”

The study listed a 96% sensitivity of the Oura ring to detect sleep, which is impressive, in the study population of 41.

I personally have no complaints about sleep duration detection from my own experience with the smart ring; the Oura ring is pretty much spot on most of the time with the rare missteps.

Yet the same study listed the agreement of 65%, 51%, and 61%, in detecting “light sleep” (N1), “deep sleep” (N2 + N3), and REM sleep when analysed epoch by-epoch compared against Polysomnography.

oura ring sleep analysis

To a layman like me, that sounded like the equivalent of a pedometer counting 6500 steps when I’ve clocked 10,000. And when the price of $300 is taken into consideration for the standard ring model, this white elephant in the room needs to be addressed – is the level of sleep stages measurement accurate by scientific benchmarks?

Perhaps my interpretation of the study is incorrect but I needed clarification. I contacted Oura support and a nice rep replied about a week later that they were getting a lot of queries but she’d link me up with someone from the research team.

I waited another two weeks since then and haven’t heard from Oura.

oura ring RHR and HRV

Granted Oura did mention a small sample size validation studies for their nocturnal HRV values and body temperature, I still had nagging queries about sleep stages accuracy and also what further sleep validation studies the company has up its sleeves.

After all, the company did state on their website that they will release further validation reports soon.

Here are all the validation studies I can find. If you are going to splurge and change your sleep habits based on a $300 wearable, I recommend you read through these studies carefully:

  1. The Sleep of the Ring: Comparison of the ŌURA Sleep Tracker Against Polysomnography
  2. The HRV of the Ring – Comparison of nocturnal HR and HRV between the ŌURA ring and ECG
  3. Sleep Lab validation of a wellness ring in detecting sleep patterns based on photoplethysmogram, actigraphy and body temperature


The Oura ring does provide some insights into how the body is functioning and its state of recovery.  After a tough and long workout, the readiness readings would dive followed by a gradual climb over 1-2 days. A less than ideal sleep would bring up some advice from the Oura app telling you what may have hampered your sleep quality and tips to get better shut-eye – basically personalised guidance. The smart ring also doubles up as an activity tracker and does a decent job tracking steps and active periods in a day.

These features might be attractive to some consumers since the device is ring-like and not a sporty looking band or watch.

The current wave of wearables are already pushing out their own sleep tracking algorithms with their hardware; think Garmin’s advanced sleep, Polar’s Sleep Plus, or Fitbit’s Sleep Stages.

You’ll also have to bear in mind that at $300, you can easily buy one of the wearables from the companies I listed above and you’ll get a superior activity tracking experience compared to what the Oura ring can offer alone.

The new Oura ring is endowed with numerous features in a tiny package but until Oura releases more research or validation reports, I’m inclined to take their “world’s most advanced wearable for restorative sleep” claim with a pinch of salt.


  • Reply Oura Ring 2018 – Smart Ring Wearable – User Review | GadFit – August 30, 2018 at 6:06 pm

    […] The new Oura ring is quantum leaps ahead of the first generation ring by the same name. For starters, the company reduced the physical size of their smart ring to something more sensibly palatable. Pe… (read orginal – story…) […]

  • Reply SWLinPHX October 20, 2018 at 7:25 am

    ERROR: Your sleep tracking algorithm links for different hardware include the Polar Sleep Plus link twice (in place of the Fitbit’s Sleep Stages.

    • Reply Michael S October 20, 2018 at 9:31 am

      Updated. Thanks for the bringing it up.


  • Reply Barnett Lee November 3, 2018 at 10:07 pm

    Thanks so much for the review. It’s refreshing. Other reviews I found online seemed biased as it was affiliate marketing. Yours is the only one I’ve seen that points out some inaccuracies from the device.

    How long did the ring take to be received? I’ve read on Reddit that the waitlist is long and some have been waiting for more than half year for theirs.

    Thanks so much


    • Reply Michael S November 4, 2018 at 9:45 am

      Hi Barnett,

      Glad to hear you found the review useful. I’m still using the Oura ring to date – specifically looking at duration of sleep and RHR.

      I waited longer than usual because of the approval Oura needed to send the item to Singapore. I ordered in November 2017 and received the ring in August this year; I was given a big discount as I funded the original Oura ring when they crowdfunded.

      From what I understand, the company states shipping date at 8 week now.

      Hope that helps.

  • Reply Bill November 29, 2018 at 7:24 am

    How accurate do you find the fitness tracker and the steps counter? I’ve had my ring for about 11 days now and it always records way more steps than other apps, even when I make notes of the numbers before and after a hike. The differences make me wonder about some of the accuracy of the whole ring, although I do feel good about the info i’m getting so far.

    • Reply Michael S November 29, 2018 at 10:38 am

      Hi Bill,

      Specifically for the step tracker feature, it is always higher than that recorded by a wrist worn wearable based on my own usage. Hope that helps.


  • Reply Georgi December 16, 2018 at 11:35 am

    Great review, the most helpful I read so far.Placed an order and waiting.

  • Reply Dave Baker February 9, 2019 at 6:43 am

    The sleep stages are way off for me. By miles as is the steps counter. In fact a total waste of time. My Gear Fit is a lot more accurate. The HRV seems good though I’ve got nothing to check it against. Oura themselves are terrible at customer service and simply need to employ more people

    • Reply Michael S February 9, 2019 at 10:07 am

      Thanks for your comments Dave.

  • Reply Bjorn Lee March 26, 2019 at 11:55 pm

    I’m seeking a ring for scientific research purposes at a sleep lab in Singapore. Know anyone who wants to get rid of the Oura 2 ring? Happy to get a used working one rather than wait 8-12 weeks according to the website.

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