15-month-old sleep schedule

At a glance

Sleep in 24 hours: consensus of the American sleep physicians (AASM, Paruthi 2016) – a value for groups, not for an individual child.

Night: this is what Moon Hour starts out with and then learns your child’s night length.

An example day

This is how Moon Hour might calculate on the first day if a child at 15 months wakes at 7 am and has no entries yet. It is an example, not a plan to follow: children are different, and the app adjusts the times to your child with every entry. Sleep schedule calculator: an example day for your wake-up time

Sleep schedule as a printable PDF (A4)

What often changes at 15 months

From 15 months, Moon Hour accounts for one nap; in a long-term study, a single afternoon sleep had usually settled in between 15 and 24 months (Weissbluth 1995). At the change from two naps to one, children in app data made up about four fifths of the lost sleep with a longer nap (Paavonen 2026). If your child still takes two naps, you set the number in the app.

If you are worried

Experts recommend contacting your paediatrician or your local out-of-hours medical service if you are worried.