Time & Date
Sleep Time Calculator
Lets users convert and compute sleep time instantly with formula, steps and examples — no manual math.
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h
min
Your result
Ideal bedtime (6 cycles)
9:15 PM (6 cycles, 9h)
For a 6:30 wake-up, aim to be asleep by one of these times to wake between sleep cycles.
Alternative (5 cycles)
10:45 PM (5 cycles, 7.5h)
About this calculator
Sleep happens in ~90-minute cycles; waking at the end of a cycle feels more refreshing than mid-cycle. This suggests bedtimes for 5–6 full cycles before your wake time, allowing time to fall asleep.
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