Sleep Cycle Calculator
Find bedtimes that let you wake at the end of a sleep cycle.
23:15
recommended bedtime (5 cycles / 7.5 hours)
- 6 cycles — 9 hours
- 21:45
- 5 cycles — 7.5 hours
- 23:15
- 4 cycles — 6 hours
- 00:45
- 3 cycles — 4.5 hours
- 02:15
Includes roughly 15 minutes to fall asleep.
Formula: 90-minute sleep cycles plus fall-asleep time
About this calculator
- Sleep cycles average about 90 minutes but vary between individuals and across the night.
Disclaimer: This content is provided for general educational purposes only and is not medical advice, diagnosis, or treatment. Always consult a qualified healthcare professional before making decisions about your health, exercise, or nutrition.