Sleep Cycle Calculator

I am 25 years old

I want to wake up at 7:30

When should I go to bed?

To wake up at 7:30, you should go to bed at:
22:30SUGGESTED 9 hours of sleep, 6 sleep cycles
0:00SUGGESTED 7.5 hours of sleep, 5 sleep cycles
1:30 6 hours of sleep, 4 sleep cycles
3:00 4.5 hours of sleep, 3 sleep cycles
If you wake up at one of these times, you should wake up at the end of a sleep cycle in your lightest sleep phase feeling most refreshed.

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What is a Sleep Cycle?

As you sleep, your brain goes through various, repeating patterns of activity. Whenever a pattern starts again, that is the beginning of a new sleep cycle. There are two sleep cycle categories, REM and non-REM (NREM) sleep.

Non-REM sleep happens first and includes three to four stages. You sleep deeply in the last stages of non-REM sleep and it is hard to wake up from this stage of sleep.

REM sleep happens about an hour to an hour and a half after falling asleep. REM sleep is when you tend to have vivid dreams and this is the most likely period to briefly wake up at night.