The Oura Ring is a smart ring sleep tracker wearable developed by Oura Health, a startup based in Finland.
Tracks sleep cycles (light sleep, REM sleep, Deep sleep)
Tracks resting heart rate (only during sleep) and heart rate variability (an important metric for recovery)
3D motion (activity tracker, steps taken)
Bluetooth syncs data to Oura Ring app (iPhone and Android).
Charges wirelessly through an included charging base.
Battery lasts up to 7 days on a single charge.
Water resistant up to 100 m.
App calculates a "Readiness Score" and a "Sleep Score" based the data collected from sensors
Sensor data accessible on Oura Cloud website.
Heart Rate (infrared optical pulse), Heart Rate Variability (HRV), Body Temperature, 3D movement (gyro)
Wireless Bluetooth Low Energy Smart
Wireless, USB-C connection
Titanium, diamond-like carbon coating
4 - 6 grams
US 6 - 13 ring size, 7.9mm wide, 2.55 mm thick
Silver, Black, Rose Gold, Stealth Black
Ah, the Oura ring.
Nothing says Silicon Valley biohacker status symbol more than this sleep tracker disguised as a chunky fashion accessory. It's expensive -- that's for sure -- coming in at nearly the price of an Apple Watch ($300 USD, not counting customs fees for which this unfortunate Canadian was dinged an extra $50) and it doesn't even track your heart rate 24/7 or receive phone calls!
So why did I buy it and why do I see so many people wearing them at biohacker meetups?
Well, when it comes to measuring heart rate variability (HRV) and total sleep in a simple unobtrusive manner, nothing really comes close to the Oura ring.
I briefly contemplated getting a Fitbit but it uses a heart rate sensor that constantly flashes a bright green LED -- which could interfere with your circadian rhythm. Fitbits are also kinda bulky.
The Motiv Ring, a close competitor, while cheaper than the Oura ring lacks the ability to measure HRV, which is important metric I use to judge whether I am recovered enough to attempt deadlifts on the day.
Until Apple comes out with a watch that is extremely light, has built in sleep tracking, and only needs to be charged once a week, I'm sticking with the Oura ring.
Sleep stages accuracy
I would not trust the Oura ring for accurate measures of REM or Deep sleep. The only scientific study that measured the Oura ring vs a PSG (polysomnography, the gold standard used in sleep clinic labs) was not very impressive, showing something like only 50% - 60% agreement for sleep stages (for Oura ring v1). The Oura Total sleep time was much better at roughly 90% agreement.
If you really want to track your sleep stages you probably will need to buy a sleep tracker with EEGs, such as the Dreem 2.