Sleep Calculator
Find the best time to sleep or wake up based on 90-minute sleep cycles. Get 5-6 complete cycles for optimal rest and energy
Based on 90-minute sleep cycles (15 min to fall asleep)
02:15
✗ Minimal (3 cycles)
4h 45m
3 cycles
00:45
⚠ Fair (4 cycles)
6h 15m
4 cycles
23:15
✓ Good (5 cycles)
7h 45m
5 cycles
21:45
✓ Optimal (6 cycles)
9h 15m
6 cycles
💡 Sleep Tips
- • Aim for 5-6 complete cycles for best rest
- • One 90-minute cycle includes all sleep stages
- • 4 cycles is the minimum for feeling rested
- • Less than 3 cycles may cause grogginess
- • Keep your bedtime and wake time consistent
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