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How Many Hours of Sleep Do You Need?

Sleep need changes by age and by person. Cycle math helps with timing, but total sleep duration still matters.

Age groupTypical targetCycle example
Teens 13-178-10 hours6 cycles = 9 hours
Adults 18-647-9 hours5 cycles = 7.5 hours
Adults 65+7-8 hours5 cycles = 7.5 hours