How much sleep did you get last night? What about the night before? Keeping track of your sleep schedule may not be a top priority, but getting enough sleep is critical to your health in many ways.
You may not realize it, but the amount of sleep you get can affect everything from your weight and metabolism to your brain function and mood.
For many people, wake-up time is a constant. What time you go to sleep, however, tends to vary depending on your social life, work schedule, family obligations, the newest show streaming on Netflix, or simply when you start to feel tired.
But if you know what time you have to get up, and you know you need a specific amount of sleep to function at your best, you just need to figure out what time to go to bed.
In this article, we’ll help you understand how to calculate the best time to go to bed based on your wake-up time and natural sleep cycles. We’ll also take a closer look at how your sleep cycles work and how sleep can affect your health.
How much sleep you need changes throughout your lifetime. An infant may need up to 17 hours of sleep each day, while an older adult may get by on just 7 hours of sleep a night.
But an age-based guideline is strictly that — a suggestion based on research of how much sleep you may need for optimal health as your body’s needs change.
According to the National Sleep Foundation, these are the general sleep guidelines for different age groups:
Everyone’s sleep needs are different, even within the same age group. Some people may need at least 9 hours of sleep a night to feel well-rested, while others in the same age group may find that 7 hours of sleep is just right for them.
Bedtimes are based on:
|Wake-up time||Bed time:
7.5 hours of sleep
9 hours of sleep
|4 a.m.||8:15 p.m.||6:45 p.m.|
|4:15 a.m.||8:30 p.m.||7 p.m.|
|4:30 a.m.||8:45 p.m.||7:15 p.m.|
|4:45 a.m.||9 p.m.||7:30 p.m.|
|5 a.m.||9:15 p.m.||7:45 p.m.|
|5:15 a.m.||9:30 p.m.||8 p.m.|
|5:30 a.m.||9:45 p.m.||8:15 p.m.|
|5:45 a.m.||10 p.m.||8:30 p.m.|
|6 a.m.||10:15 p.m.||8:45 p.m.|
|6:15 a.m.||10:30 p.m.||9 p.m.|
|6:30 a.m.||10:45 p.m.||9:15 p.m.|
|6:45 a.m.||11 p.m.||9:30 p.m.|
|7 a.m.||11:15 p.m.||9:45 p.m.|
|7:15 a.m.||11:30 p.m.||10 p.m.|
|7:30 a.m.||11:45 p.m.||10:15 p.m.|
|7:45 a.m.||12 p.m.||10:30 p.m.|
|8 a.m.||12:15 a.m.||10:45 p.m.|
|8:15 a.m.||12:30 a.m.||11 p.m.|
|8:30 a.m.||12:45 a.m.||11:15 p.m.|
|8:45 a.m.||1 a.m.||11:30 p.m.|
|9 a.m.||1:15 a.m.||11:45 p.m.|
When you fall asleep, your brain and body go through several cycles of sleep. Each cycle includes four distinct stages.
The NREM stages used to be classified as stages 1, 2, 3, 4, and REM. Now, the National Sleep Foundation classifies them this way:
It takes, on average, about 90 minutes to go through each cycle. If you can complete five cycles a night, you’d get 7.5 hours of sleep a night. Six full cycles is about 9 hours of sleep.
Ideally, you want to wake up at the end of a sleep cycle instead of in the middle of it. You usually feel more refreshed and energized if you wake up at the end of a sleep cycle.
Sleep is crucial for many reasons. A good night’s sleep:
To improve your sleep health, consider the following tips.
If you’re aiming for 7 to 9 hours of sleep each night, a sleep calculator can help you figure out what time to go to bed based on your wake-up time. Ideally, you’ll want to wake up at the end of your sleep cycle, which is when you’re most likely to feel the most rested.
A good night’s sleep is essential to good health. If you’re have trouble falling asleep or staying asleep, consider talking to your doctor. They can help determine if there’s an underlying cause.