How long should your baby stay awake?

Persistent nap resistance has three common causes. One, the wake window is too short — babies under 4 months especially need active soothing to fall asleep, not necessarily a longer awake interval. Two, the wake window is too long and overtired hormones (cortisol) are blocking sleep. Three, the sleep environment has shifted — too bright, too warm, no white noise. Try the lower bound of the wake window for a few days first. If that fails, try the upper bound. If both fail, look at environment.

Most often between 13 and 18 months. Signs your child is ready: the second nap pushes bedtime later than 8 PM, both naps shorten to under 45 minutes, or your child fights the second nap entirely on most days. The transition itself takes 4 to 6 weeks. During the gap, an earlier bedtime (around 6:30 PM) bridges the missed afternoon sleep.

Anywhere from 2.5 to 5 years. The signal is consistent: nap is making bedtime late (past 9 PM), nap is fragmented or short, and your child is not visibly cranky on no-nap days. Drop gradually — alternating nap and no-nap days for a few weeks works better than abrupt cessation. Replace the nap slot with quiet rest time to preserve the wind-down ritual.

Use the next band as a comparison. The transitions between bands are gradual — a 5.5-month-old will look more like a 6-month-old than a 4-month-old. If your child consistently extends to the upper edge of their band's wake window, they are likely ready for the next band's lower edge. Watch sleep cues for two weeks before formally adjusting the schedule.

Use adjusted age, not chronological. A baby born 8 weeks early at 6 months chronological should follow the 4-month band until their adjusted age catches up. Most pediatricians stop adjusting around 2 years. If your baby was very preterm, ask your pediatrician for personalised guidance — the bands here assume term-baby development.

The AAP 2016 sleep duration consensus statement is the primary source — it endorsed the National Sleep Foundation 2015 ranges with minor adjustments. Those are the figures used here: 14–17 hours for newborns, 12–15 hours for infants 4–11 months, 11–14 hours for toddlers 1–2 years, 10–13 hours for preschoolers 3–5 years.