Sleep Calculator
Find the best bedtime or wake-up time based on 90-minute sleep cycles for optimal rest.
6 cycles (9.0h)
9:45 PM
Recommended
5 cycles (7.5h)
11:15 PM
Recommended
4 cycles (6.0h)
12:45 AM
3 cycles (4.5h)
2:15 AM
Recommended Bedtimes
| 6 sleep cycles | 9:45 PM (9.0 hours) |
| 5 sleep cycles | 11:15 PM (7.5 hours) |
| 4 sleep cycles | 12:45 AM (6.0 hours) |
| 3 sleep cycles | 2:15 AM (4.5 hours) |
Each sleep cycle is approximately 90 minutes. Waking between cycles helps you feel more rested. An average of 15 minutes to fall asleep is included in calculations.
Use the Sleep Calculator above to calculate your results. Enter your values and see instant results — all calculations run in your browser.
Disclaimer: This calculator is for informational purposes only and does not constitute tax, financial, or legal advice. Results are estimates based on the information you provide and current rates. Always consult a qualified tax professional or financial advisor for advice specific to your situation.
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