Is 9 Hours of Sleep Enough?
Nine hours of sleep is at the upper end of what adults need: the National Sleep Foundation recommends 7 to 9 hours. It can be right for young adults, teenagers and anyone recovering from sleep debt or illness.
Bedtimes for 9 hours of sleep
Each bedtime includes 15 minutes to fall asleep.
Enough for adults?
Usually more than you need
Sleep cycles
6
Sleep debt per week vs. 7 h
None
| To wake up at | Go to bed at |
|---|---|
| 5:30 AM | 8:15 PM |
| 6:00 AM | 8:45 PM |
| 6:30 AM | 9:15 PM |
| 7:00 AM | 9:45 PM |
| 7:30 AM | 10:15 PM |
| 8:00 AM | 10:45 PM |
Want a different wake-up time? The sleep calculator finds bedtimes that end on a full sleep cycle.
What the research says about 9 hours of sleep
Nine hours is exactly six full sleep cycles, so waking is usually easy. If you regularly need much more than 9 hours to feel rested, it can point to poor sleep quality, such as sleep apnea, and is worth raising with a doctor.
How much sleep you need by age
These are the National Sleep Foundation's recommended ranges.
| Age | Hours per night |
|---|---|
| School-age children (6–13) | 9–11 |
| Teenagers (14–17) | 8–10 |
| Adults (18–64) | 7–9 |
| Older adults (65+) | 7–8 |
Other sleep lengths
- Is 3 hours of sleep enough?
- Is 4 hours of sleep enough?
- Is 5 hours of sleep enough?
- Is 6 hours of sleep enough?
- Is 6.5 hours of sleep enough?
- Is 7 hours of sleep enough?
- Is 8 hours of sleep enough?
Running short most nights? The sleep debt calculator shows how much you owe and how long it takes to pay back.
More free sleep tools
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Nap Calculator
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Sleep Debt Calculator
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REM Sleep Calculator
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Jet Lag Calculator
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Sleep Efficiency Calculator
What share of your time in bed you actually spend asleep.
Sleep Schedule Calculator
A day-by-day plan to fix your sleep schedule or adjust to daylight saving time.
Caffeine Calculator
How much caffeine is left at bedtime and when to have your last coffee.
Chronotype Quiz
Five questions to find out if you are a morning lark or a night owl.
Frequently asked questions
Is 9 hours of sleep enough?
Nine hours of sleep is at the upper end of what adults need: the National Sleep Foundation recommends 7 to 9 hours. It can be right for young adults, teenagers and anyone recovering from sleep debt or illness.
How many sleep cycles is 9 hours of sleep?
Exactly 6 sleep cycles of about 90 minutes, so waking at the 9-hour mark usually lands in light sleep.
What time should I go to bed to get 9 hours of sleep?
Count back 9 hours and 15 minutes from your alarm. To wake at 7:00 AM, go to bed at 9:45 PM.