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Time, Date & Personal Calculator
Sleep Calculator
Calculate suggested bedtimes or wake-up times from sleep cycles, cycle length and time needed to fall asleep.
Sleep cycle bedtime and wake-up calculator
90 minutes is a common average.
4 cycles–
5 cycles–
6 cycles–
Mode–
Enter a wake-up time or bedtime to calculate sleep cycle suggestions.
Sleep cycle formula
Bedtime = wake-up time – fall asleep time – (cycles x cycle length)
Wake-up time = bedtime + fall asleep time + (cycles x cycle length)
Sleep cycles vary by person and night. This calculator uses cycles as a planning estimate, not a medical diagnosis.
How to use sleep cycle results
- Five or six cycles is a common target for many adults.
- Keep a consistent wake time when possible.
- Give yourself wind-down time before the suggested bedtime.
- If sleep problems are persistent, speak with a qualified healthcare professional.
Sleep Calculator FAQ
How long is a sleep cycle?
A common average is about 90 minutes, but real sleep cycles vary by person and night.
Should I choose 4, 5 or 6 cycles?
Many adults aim for 5 or 6 cycles. Four cycles may be short for regular sleep.
Does this include time to fall asleep?
Yes. Enter your estimated sleep latency and the calculator includes it.
Can this fix insomnia?
No. It is a planning tool. Persistent sleep issues should be discussed with a healthcare professional.
Why are some times on the previous day?
When calculating bedtimes from a morning wake time, suggested bedtimes may fall on the previous evening.
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