Waking up at the wrong time can ruin your day. The sleep calculator provides you with multiple times to choose from, enabling you to wake between sleep cycles so can you be at your best with the time you have available. 7 hours is generally the recommended amount of sleep for healthy adults. See the directions below for more information.

Falling asleep at {{ clock_time | date:'shortTime' }}, the best times to wake up:
Time to Wake UpLength
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To wake up at {{ clock_time | date:'shortTime' }}, the best times to fall asleep:
Time to Fall AsleepLength
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Still feeling tired?

Keep in mind that the average length for the subsequent cycles of sleep are typically between 100 and 120 minutes long. Your sleep cycles may be longer or shorter than average and you may need to experiment with the length of the non-initial cycle, taking note of how you feel in the mornings.

Purpose of the Calculator

The calculator makes it dead simple to figure out what times you should be sleeping. It can provide the perfect bedtime or wake up time based on your schedule. Sleeping at the proper times can reduce or eliminate morning grogginess, also known as sleep inertia. It is what ruins most people's mornings, robbing them of productivity, lost time due to numerous alarm resets, interpersonal problems, memory difficulty and poor performance in general. Avoid the snooze button and take back your mornings.

While we can't guarantee you will wake between cycles, we can get close. The app uses average or customized sleep cycle lengths to calculate the time tables. To wake up feeling refreshed you need to wake in between sleep cycles, not during one. It takes approximately 90 minutes to have your first complete sleep cycle and each subsequent cycle lasts an average of 110 minutes (Source - Sleep: Physiology, Investigations, and Medicine). A full night's rest is typically 4 cycles for an adult and more for children depending on age. Keep in mind that it takes approximately 15 minutes to fall asleep when scheduling your sleep.

How Much Sleep do you need?

Getting the proper amount of sleep and waking up at the right time is what we are all about. Consult the table below to see how much sleep your body needs and then use the sleep calculator to wake up at the right time. Everyone wants to feel refreshed and alert instead of groggy and upset.

Amount of Sleep Required by Age
AgeAmount of Sleep
Newborns 16 - 18 hours
Children (2-5 yrs)11 - 12 hours
Elementary Age (5-10 yrs)at least 10 hours
Adolescents (11-17 yrs)9 - 10 hours
Adults (17+ yrs)around 7 hours (7-8)

source: NIH - National, Heart, Lung and Blood Institute

Rest and renewal only comes during the REM stages, the more rest you need translates in to needing more time spent in the REM stages of sleep. Each person is different depending on their age but in general, healthy adults need around 7 hours of sleep per night, with children and older people needing more. Teens typically need nine or more hour per evening, with younger children needing ten to fifteen hours for restoration. Younger people are still growing and it typically takes more sleep to recover, increase in size, and also deal with hormonal changes. As a person that isn't afflicted with any illness, oversleeping can negatively affect how your body and mind perform the next day as much as not getting enough. When you first awaken, take stock of how you feel. If you wake naturally, don't try to a few more winks; go ahead and get out of bed. Going back to sleep can actually make you feel worse.

If you are wanting to take a nap you should only sleep for and hour and a half, which is one cycle. If you can't sleep 90 minutes, only keep your eyes closed but lay horizontally to relieve your blood pressure and to reduce the stress on your body. This has been shown to reduce heart attacks and is quite common in Latin and European countries that have a split day sleeping pattern of five to six hours and night and sixty to ninety minutes in the afternoon.

How to use the Sleep App

Before hitting the hay, consult the webapp. It works on phones, tablets and desktops. The clock is used to generate two different types of time tables, one if you want to know when to set your alarm and one for when to head to bed. Enter the desired time for either falling asleep or waking up. Adjust length of the subsequent sleep cycles as needed (by default it is set at the average). The customized tables adjust automatically to your input.