Sleep Calculator
Calculate the best time to go to bed based on sleep cycles. Wake up refreshed and energized.
How It Works
Sleep occurs in 90-minute cycles. The calculator works backward from your wake time to find optimal bedtimes. We add 14 minutes to account for the time it takes to fall asleep.
Example
If you need to wake up at 7:00 AM, going to bed at 10:30 PM gives you 5 sleep cycles (7.5 hours) plus 14 minutes to fall asleep.
Frequently Asked Questions
How does the sleep calculator work?
Sleep occurs in 90-minute cycles. The calculator works backward from your wake time to find optimal bedtimes that align with complete sleep cycles.
How many sleep cycles do I need?
Most adults need 4-6 sleep cycles per night (6-9 hours). 5 cycles (7.5 hours) is often recommended for optimal rest and alertness.
Why is waking up at the end of a cycle important?
Waking up at the end of a sleep cycle helps you feel refreshed. Waking mid-cycle can cause grogginess and sleep inertia.