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😴 Sleep Calculator
90-minute cycles plus 15 minutes to fall asleep. A rule of thumb, not a clinic.
FAQ
Why 90 minutes?
A common estimate for one sleep cycle. Real cycles vary. This page adds 15 minutes to fall asleep.
How many cycles should I sleep?
Five or six (about 7.5–9 hours plus fall-asleep time) is the usual target. Pick what you can keep.
Is this medical advice?
No. It is a bedtime/wake arithmetic helper.