Sleep Cycle Calculator
Find the best time to go to bed based on your wake-up time and 90-minute sleep cycles.
Inputs
Results
Bedtime for 6 cycles (9 hrs)
9:45 PM
Bedtime for 5 cycles (7.5 hrs)
11:15 PM
Bedtime for 4 cycles (6 hrs)
12:45 AM
How it's calculated
Working back from your wake-up time in 90-minute sleep cycles (plus about 15 minutes to fall asleep), it suggests bedtimes that let you complete 4, 5, or 6 full cycles.
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