TryVibes
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Health

Sleep Calculator

Find the best time to sleep or wake up based on sleep cycles

Recommended Bedtimes

9:45 PM

6 cycles · 9 hours of sleep

Recommended

11:15 PM

5 cycles · 7.5 hours of sleep

Good

12:45 AM

4 cycles · 6 hours of sleep

OK

2:15 AM

3 cycles · 4.5 hours of sleep

Minimum

Includes ~15 minutes to fall asleep

Sleep Cycles

1
2
3
4
5
6
9:45 PM7:00 AM
Sleep Tips
  • Keep a consistent sleep schedule, even on weekends
  • Avoid screens (phone, computer, TV) 30-60 minutes before bed
  • Keep your bedroom cool (65-68°F / 18-20°C) and dark
  • Avoid caffeine at least 6 hours before bedtime
  • Exercise regularly, but finish at least 3 hours before bed
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Sleep Calculator

Find the best time to go to bed or wake up with this free sleep cycle calculator. It works in 90-minute sleep cycles so you wake at the end of a cycle feeling refreshed instead of groggy. Enter a wake-up time to see ideal bedtimes, or a bedtime to see when to set your alarm.

FAQ

How does the sleep calculator work?
A full sleep cycle lasts about 90 minutes. The calculator counts back or forward in 90-minute blocks so your alarm lands at the end of a cycle rather than mid-cycle.
How many sleep cycles do I need?
Most adults need five to six complete cycles per night, roughly 7.5 to 9 hours of sleep, plus about 15 minutes to fall asleep.
Why do I wake up tired even after 8 hours?
Waking in the middle of a deep-sleep stage causes grogginess. Aligning your alarm with the end of a cycle helps you wake more easily.