Sleep Calculator
Find the best bedtime or wake-up time based on 90-minute sleep cycles
Wake-up times are calculated from the current time.
Result
About sleep cycles
Sleep repeats in cycles of about 90 minutes. Waking up at the end of a cycle makes it easier to feel refreshed. Most adults do best with 5 to 6 cycles (about 7.5 to 9 hours) per night. Results are for reference only.