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Sleep Cycle Planner

Choose whether you know your planned wake-up time or bedtime, specify how long you typically take to fall asleep, and select how many 90-minute cycles you want to complete. The calculator suggests optimal schedules to reduce grogginess.

Enter a valid wake-up time to see suggested bedtimes.

How to Use This Calculator

1

Pick your mode

Choose whether you know your wake-up time (plan bedtime) or your bedtime (plan wake time).

2

Enter timing details

Provide the anchor time and how many minutes you typically need to fall asleep. Adjust which cycles to include.

3

Review recommended schedules

Choose the bedtime or wake time that best fits your routine. Aim for sufficient total sleep time alongside aligned cycles.

Formula

Bedtime = Wake-up time − (Cycles × 90 min + Minutes to fall asleep)

Wake time = Bedtime + (Cycles × 90 min + Minutes to fall asleep)

Completing full sleep cycles reduces the likelihood of waking during deep sleep. However, total sleep quantity and regular schedules remain the most vital factors for restorative rest.

Sleep Hygiene Tips

Environment

  • Keep the bedroom cool, dark, and quiet.
  • Reserve the bed for sleep and intimacy only.
  • Use blackout curtains or an eye mask if needed.

Routine

  • Maintain consistent sleep and wake times, even on weekends.
  • Avoid caffeine after mid-afternoon and heavy meals before bed.
  • Wind down with relaxing activities and limit bright screens.

Frequently Asked Questions

Is a 90-minute cycle always accurate?

Sleep cycles average about 90 minutes but fluctuate between 70 and 110 minutes. Use the calculator as a guideline and adjust based on how refreshed you feel.

What if I cannot fall asleep at the suggested time?

Start winding down earlier with a calming routine. If long sleep latency persists, consult a sleep specialist or explore cognitive behavioral therapy for insomnia (CBT-I).

How much total sleep do I need?

Most adults require 7–9 hours nightly. Teenagers need 8–10 hours and young children require more. Prioritize total sleep quantity alongside cycle alignment.

Can naps replace lost nighttime sleep?

Short naps can boost alertness but do not fully substitute for consolidated nighttime sleep. Avoid napping late in the day to protect bedtime.