Sleep Calculator
Plan a Full Night of Sleep
Choose when you need to wake up and see several bedtimes based on complete sleep cycles.
Enter your wake-up time, then calculate.
How the Sleep Calculator Works
The calculator counts backward in approximate 90-minute cycles and adds the time you expect to spend falling asleep. Sleep cycles vary from person to person, so use the results as planning windows rather than exact biological deadlines.
Choose a bedtime that gives you enough total sleep. Adults generally need at least seven hours, while children and teenagers usually need more.
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