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 including sleep recommendations table.

Falling asleep at {{ clock_time_w_delay | date:'shortTime' }}, the best times to wake up:

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To wake up at {{ clock_time | date:'shortTime' }}, the best times to fall asleep:

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Time to Fall AsleepLength
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Still feeling tired?

Keep in mind that this sleep calculator is based off of the average sleep cycle length of 90 minutes and based on a precise time that you are falling asleep. Adjust the delay time to add in small time that it takes for you to fall asleep after getting in bed in 5 minute increments from no delay to 30 minutes. It takes an average of 15 minutes to fall asleep, which is the default.

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 delay based on how long it takes you to fall asleep after getting in bed. By default it is set at the average which is 15 minutes. The customized tables adjust automatically to your input.

Purpose of the Calculator

The calculator makes it simple to figure out what times you should be sleeping. It provides 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. Sleep inertia 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 sleep app uses average sleep cycle lengths based on scientific studies conducted at Harvard University to calculate the time tables.

To wake up feeling refreshed you need to wake in between sleep cycles, not during one.

A full night's rest is typically 5 cycles for an adult and more for children depending on age. Keep in mind that it takes 15 minutes on average to fall asleep when scheduling your sleep. The sleep calculator features an adjustable delay feature that moves in 5 minute increments, with the default set at 15 minutes. Adjust this delay based on your personal experiences.

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, accompanied by knowledge of your requirements and then use the sleep calculator to wake up at the right time. Sleeping the amount your body requires will help you feel refreshed and alert during the day.

Amount of Sleep Required by Age
AgeAmount of Sleep
Newborns (0-3 months)14 - 17 hours
Infants (4-12 months)12 - 16 hours
Toddler (1-2 yrs)11 - 14 hours
Pre-School (3-5 yrs)10 - 13 hours
Elementary Age (6-12 yrs)9 - 12 hours
Teens (13-18 yrs)8 - 10 hours
Adults (18-64 yrs)7 - 9 hours
Older Adults (65+ yrs)7 - 8 hours

source: CDC recommendations

While most people will fall in the average time that is recommended, there is a small buffer zone of roughly an hour on either side of the recommendations.

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 teens 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 sleep. 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 an hour and a half, which is one cycle max. If you can't sleep 90 minutes, try to wake after 20 to 30 mins before falling into a deep sleep. You can also just 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.