Wake up feeling refreshed by aligning your alarm with your natural 90-minute sleep cycles.
4 Cycles (6 Hours):
18:45
5 Cycles (7.5 Hours):
23:15
6 Cycles (9 Hours):
03:45
Note: Waking up at the end of a 90-minute cycle prevents sleep inertia and grogginess.
The human body sleeps in cycles averaging 90 minutes, moving through light, deep, and REM sleep.
Formula: Wake Time = Bedtime + (90min × Cycles) + Latency
Wake Time = Bedtime + (90min × Cycles) + Latency
If you set your 'Target Time' for bed at 11:00 PM and take 15 minutes to fall asleep.
Waking up during deep sleep often causes 'sleep inertia,' leaving you feeling groggy and tired for hours.
Most adults function best with 5 to 6 full cycles (7.5 to 9 hours) per night.
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