8-9 hours.

Newborns to 3 months: 14–17 hours

Infants 4–12 months: 12–16 hours

Young children 1–5 years: 10–13 hours

School-aged children 6–12 years: 9–12 hours

Teenagers 13–18 years: 8–10 hours

Adults 18–64 years: 7–9 hours

Adults 65 years and older: 7–8 hours