Two devices, one place
How much deep sleep do you need on Apple Watch or Oura?
Updated · 4 min read
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Short answer
There is no agreed number. Adults typically spend 10% to 20% of the night in deep sleep: 42 to 84 minutes of a 7-hour night. Check yours on Apple Watch or Oura.
Apple Watch and Oura estimate your deep sleep each night, and the Sleep Foundation says that there is no consensus on how much is ideal. Its range for an 8-hour night is 48 to 96 minutes, and deep sleep decreases as you get older.
How much deep sleep adults get
Deep sleep is what a sleep lab calls N3. N3 is stage 3 of non-REM sleep, the sleep without rapid eye movement (REM). Deep sleep is also called slow-wave sleep. Apple Watch labels it Deep. Apple Watch calls N1 and N2, the lighter non-REM stages, Core.
These are the figures that each source gives:
| Source | Deep sleep |
|---|---|
| Sleep Foundation | 10% to 20% of the night, typical for adults |
| Apple's test nights, scored by sleep technologists | 12.8% of sleep on average, over 299 nights from 166 participants with an average age of 47 |
| Oura | Anywhere from 0% to 35% of total sleep |
Oura's range is wider than the Sleep Foundation's. The National Institutes of Health (NIH) says that most adults need 7 to 9 hours of sleep a night in total, and that no amount of sleep works for everybody of the same age.
Age changes the amount. The Sleep Foundation says that children and adolescents need the most deep sleep, and that deep sleep then decreases into older age, with a gradual decline that levels off in your 70s. Oura's sleep score article says that, ideally, young adults get 90 minutes of deep sleep and older people 45 minutes. For a young adult, 90 minutes is more than the Sleep Foundation's 42 to 84 minutes for a 7-hour night.
See your deep sleep
On Apple Watch
- Open the Sleep app.
- Turn the Digital Crown to see your sleep stages for the last 14 days.
On iPhone in Health
- Open the Health app.
- Tap Browse then Sleep then Sleep.
Step 2
Where to tap
- Browse
- Sleep
- Sleep
- Tap W at the top of the chart to see the past week. Tap M or 6M to see the past month or 6 months.
- Tap Show More Sleep Data. Tap Stages to see the time and percentage that you spent Awake and in REM, Core and Deep sleep.
In the Oura app
- Open the Oura app.
- Tap the sleep shortcut at the top of the Today tab. Oura says that this opens a detailed view of your Sleep Score.
- In the Sleep detail view, find your sleep stages in color at the top of the screen.
- Scroll to Details for the hypnogram, a graph of your stages across the night.
Check your number against the range
Compare the Deep percentage in Health with the Sleep Foundation's 10% to 20%. For minutes, multiply your time asleep in minutes by 0.1 and by 0.2. Oura exports sleep stages to Apple Health on Gen3 and later rings with an active membership, so you can check Oura nights here too.
Deep sleep in each sleep score
| Apple Watch | Oura | |
|---|---|---|
| Parts of the sleep score | Sleep duration (50 points), bedtime consistency (30 points) and interruptions (20 points) | Seven contributors, one of them Deep Sleep |
| What it says about deep sleep | Apple does not list sleep stages among the parts | The Deep Sleep contributor measures the percentage of time that you spend in deep sleep |
When deep sleep happens in the night
The NIH says that deep sleep occurs in longer periods during the first half of the night. Oura says the same: usually, you get more deep sleep during the early night.
What can change the sleep stages you see
- Habits and schedule
Apple says that alcohol, caffeine, exercise, stress and an irregular schedule may influence the timing, length and stages of your sleep.
- A short night before
The NIH says that your sleep drive grows with every hour that you are awake, and that you sleep longer and more deeply after a period without sleep. The Sleep Foundation says that you might spend more time in deep sleep while you recover from a period of sleep deprivation.
- A loose watch
Apple says that if your watch is too loose, the accelerometer, the motion sensor, might register too much movement during sleep. Wear it at a comfortable fit.
- Oura numbers in Apple Health
Oura says that Apple may apply slight rounding, or draw its graphs with different time intervals. To see Oura's own figures, open the Sleep detail view in the Oura app.
Questions
Is 1 hour of deep sleep enough?
For a night of 7 or 8 hours, 1 hour is inside the Sleep Foundation's range. To work out your own range, see Check your number against the range.
Why does Apple Watch show so little deep sleep?
Apple says that the most common error of its sleep stage model is true deep sleep labeled as Core sleep. Also, Apple Watch writes stages to Apple Health only for a sleep session of more than 3 hours. For 1 to 3 hours, it writes only asleep and awake.
What if Oura shows no deep sleep at all?
Oura's Social Care Team recommends that you speak with your doctor if you consistently see very little deep sleep, or occasionally none at all. Oura's own range for deep sleep starts at 0% of total sleep. One member on r/ouraring reported 20 to 30 minutes of deep sleep on average, and zero minutes on one night.
Sources
- 1Estimating Sleep Stages from Apple Watch, Appleapple.com (opens in a new tab)
- 2Track your sleep on Apple Watch and use Sleep on iPhone, Apple Supportsupport.apple.com (opens in a new tab)
- 3Track your sleep on Apple Watch, Apple Watch User Guide, Apple Supportsupport.apple.com (opens in a new tab)
- 4Sleep Stages, Oura Member Caresupport.ouraring.com (opens in a new tab)
- 5Sleep Score, Oura Member Caresupport.ouraring.com (opens in a new tab)
- 6Your Oura Sleep Score & How To Interpret It, Ouraouraring.com (opens in a new tab)
- 7Apple Health Integration, Oura Member Caresupport.ouraring.com (opens in a new tab)
- 8Brain Basics: Understanding Sleep, National Institutes of Healthninds.nih.gov (opens in a new tab)
- 9How Much Deep Sleep Do You Need?, Sleep Foundationsleepfoundation.org (opens in a new tab)
- 10Deep Sleep is Impossible, Reddit r/ouraringreddit.com (opens in a new tab)