Build Tool
Sleep Cycle Calculator
Wake up between 90-minute sleep cycles, not in the middle of one.
Sleep runs in roughly 90-minute cycles; waking at the end of a cycle usually feels easier than the same total sleep cut mid-cycle. Add about 15 minutes to fall asleep — if you must wake at 6:30 AM, being in bed by 9:15 PM for 6 cycles means lights out around 9:00 PM. Individual cycles vary (80–120 minutes), so use this as a guide, and keep the wake time consistent even on weekends.
General information for healthy adults — not medical advice. If you have a medical condition, are on medication, or anything feels off, talk to a doctor before acting on numbers from any calculator.
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