Baby sleep schedule: wake windows by age

It is how long a baby can comfortably stay awake between two sleeps. It grows with age: under an hour for a newborn, three to four hours by the first birthday. The point of the reference is to settle before overtiredness sets in — an overtired baby falls asleep harder, not easier.

Probably nothing. Wake windows are a range rather than a timetable, and babies differ widely within the same age. Tired cues are far more reliable: rubbing eyes, looking away, losing interest in play, getting fussy. If sleep is consistently refused at the end of the window, try the lower end of the range; if settling is hard and waking early, try the upper end.

Because there is none. In its 2016 consensus the American Academy of Sleep Medicine explicitly declined to make a recommendation below four months: the available research was not sufficient. Sites that print a number there are not taking it from data. We would rather say the norm does not exist than hand a newborn’s parent a figure to fall short of.

Transitions usually land around 3–4 months, 6–9 months, near the first birthday and around eighteen months, but they follow behaviour rather than a date. The sign is a nap being consistently refused, or the last nap starting to interfere with settling at night. A transition takes weeks, and days look inconsistent while it happens; that is normal.

Yes — mark it. For the body it is sleep, and the next wake window counts from it. That is exactly why the plan is built from real marks: ten minutes in the car shifts the whole rest of the day, and a static timetable becomes useless after it.

The tool covers roughly the first four years. Closer to three, daytime sleep disappears for many children and wake windows stop being a useful model — what remains is bedtime and total sleep across the day.