Alarm Clock Calculator
Calculate the best times to sleep and wake up based on 90-minute sleep cycles.
Sleep Settings
Average person takes 10-20 minutes to fall asleep
Quick Presets:
Best Bedtimes for
07:00
Based on 90-minute sleep cycles
Go to bed at:
08:15 PM
10h 30m of sleep
7 cycles
Recommended
09:45 PM
9h 0m of sleep
6 cycles
Recommended
11:15 PM
7h 30m of sleep
5 cycles
Recommended
12:45 AM
6h 0m of sleep
4 cycles
Minimum
Sleep Tips
- • Adults need 7-9 hours of sleep (5-6 cycles)
- • Waking between cycles helps you feel refreshed
- • Avoid screens 30 minutes before bed
- • Keep your bedroom cool and dark
- • Maintain a consistent sleep schedule
Understanding Sleep Cycles
Each sleep cycle lasts approximately 90 minutes and includes light sleep, deep sleep, and REM (rapid eye movement) sleep. Waking up at the end of a cycle, rather than in the middle, helps you feel more refreshed and alert.
4 cycles (6 hours): Minimum recommended for adults
5-6 cycles (7.5-9 hours): Optimal for most adults
7 cycles (10.5 hours): May be needed during recovery or illness