Baby Sleep Needs Calculator

Newborns (0–3 months) need 14–17 hours of total sleep per 24 hours, according to the American Academy of Pediatrics and National Sleep Foundation. This is spread across 4–5 sleep periods throughout the day and night — newborns have no circadian rhythm yet, so there's no day/night distinction to their sleep.

A wake window is the amount of time a baby can comfortably stay awake between sleep periods before becoming overtired. For a 4-month-old, that's about 1.5–2 hours; for a 10-month-old, it's 3–4 hours. Respecting wake windows reduces overtiredness, which paradoxically makes it harder (not easier) for babies to fall asleep and stay asleep.

Sleep recommendations are ranges, not targets. Some children naturally sleep slightly more or less and thrive. If your child seems rested, is growing normally, and is hitting developmental milestones, their sleep is likely fine even if it doesn't match the chart. Red flags to discuss with your pediatrician include: snoring, gasping during sleep, excessive daytime sleepiness, or significant difficulty falling or staying asleep.

Most babies transition from 3 to 2 naps between 6–8 months. The shift from 2 naps to 1 nap typically happens between 15–18 months, though some babies make this switch as early as 12 months. Signs of readiness include consistently resisting the second nap, taking a long time to fall asleep for naps, or nighttime sleep becoming disrupted.

Around 3–4 months, a baby's sleep architecture matures from two sleep states (active and quiet) to four stages similar to adult sleep, including lighter REM stages. This shift causes many babies who were previously sleeping well to start waking more frequently. It's a developmental change, not a problem — but it can be disrupted by the regression. The wake window approach and consistent soothing routines help weather it.

Significantly. Deep sleep is when the brain consolidates memories and releases growth hormone. Studies link adequate infant sleep to better language development, executive function, emotional regulation, and immune health. The AAP's strong emphasis on safe sleep environments stems partly from this — sleep quality and quantity during infancy have lifelong effects.