Health · 3 min read

Sleep Cycles and the Best Time to Wake Up

Why waking at the end of a 90-minute sleep cycle feels better, and how to plan your bedtime or wake-up time.

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You don't sleep at one steady depth — you move through cycles of light sleep, deep sleep and REM. Each full cycle lasts about 90 minutes. Waking at the end of a cycle, in light sleep, tends to feel far easier than being pulled out of deep sleep.

The 90-minute rule

Aim for a whole number of cycles. Most adults do well on 5–6 cycles (about 7.5–9 hours), plus roughly 15 minutes to fall asleep.

So if you need to be up at 7:00 am, counting back six 90-minute cycles plus 15 minutes to drift off suggests a bedtime around 9:45 pm; five cycles points to about 11:15 pm.

Sleep better, not just longer

  • Keep a consistent schedule, even on weekends.
  • Dim screens and lights in the last hour before bed.
  • Avoid caffeine late in the day and heavy meals close to bedtime.
  1. 1Choose whether you're planning a wake-up time or a bedtime.
  2. 2Enter the time.
  3. 3Pick one of the suggested times that lands on a full sleep cycle.

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