Wake Window Calculator by Age

Use the lower end of the range when your baby has been awake since a long night or skipped a feeding. Use the upper end after a solid morning and a strong wake-up cue (daylight, full feed, a real activity). When in doubt, watch your baby - rubbing eyes, zoning out, fussing at toys is "the window is closing now," not "in 30 minutes."

The last awake window before bedtime is intentionally longer than the day-time windows. Bedtime works best when the baby is just-tired-enough to fall asleep within 10-15 minutes - not exhausted. If bedtime takes longer than 20 minutes or your baby is uncharacteristically wild, the last window was probably too long, not too short.

Schedules by the clock assume every day starts identically. Real days don't: a 5 a.m. wake-up shifts everything, a long stroller nap eats the next window, daycare drop-off lands on an awkward time. Wake windows let you adapt - "she was up at 6, so the first nap is around 7:30 today" - without losing the daily total.

On the other hand, wake windows alone are not enough. Babies also need the right total daily sleep, and a stable bedtime keeps the circadian rhythm anchored. Baby Soma combines both: wake windows to time the next sleep, daily totals to flag overtired or under-tired days.

This table is a typical range, not a prescription. Some babies are at the bottom of the range from birth (low sleep need, intense temperament). Some are at the top consistently. Some go through a 2-3 week window where everything is off because of a growth spurt or a regression - that is normal and not a permanent shift.

If you find yourself fighting the range every single day for two weeks, ignore the calculator and follow your baby. The point of the calculator is to give you a starting point on day one, not to override what your specific baby is showing you on day fifteen.