Baby Wake Window Calculator
Pick your baby's age to see the typical awake stretch between sleeps, and add the last wake-up time to see when the next nap is likely to land. Ranges follow the same public guidance our month-by-month guides cite.
3-4 months: typical wake windows run 1.5 h to 2 h, with 3 to 5 naps and roughly 12 to 16 hours of total sleep per day.
Ranges are orientation, not rules: sleepy cues (zoning out, fussing, rubbing eyes) outrank the clock, and windows often lengthen across the day.
See the full wake window table by age
| Age | Wake window | Naps | Total sleep |
|---|---|---|---|
| Newborn (0-1 month) | 45 min to 1 h | 4-6 | 14-17 h |
| 1-2 months | 45 min to 1.5 h | 4-6 | 14-17 h |
| 2-3 months | 1 h to 1.5 h | 4-5 | 14-17 h |
| 3-4 months | 1.5 h to 2 h | 3-5 | 12-16 h |
| 4-6 months | 1.5 h to 2.5 h | 3-4 | 12-16 h |
| 6-9 months | 2 h to 3 h | 2-3 | 12-16 h |
| 9-12 months | 2.5 h to 3.5 h | 2 | 12-16 h |
| 12-18 months | 3 h to 5 h | 1-2 | 11-14 h |
| 18-36 months | 4 h to 6 h | 1 | 11-14 h |
How to use wake windows without living by the clock
The window is a search area, not an alarm: start the wind-down a little before it opens, then let your baby's cues decide the exact moment. Early cues look like zoning out and slowing down; late cues look like fussing, eye rubbing and jerky movements.
Two practical patterns help most families: windows usually lengthen across the day, with the last one before bedtime the longest, and a nap that ended early usually means the next window runs short.
Frequently asked questions
What is a wake window?
A wake window is the stretch of time a baby can comfortably stay awake between two sleeps, including feeding and play. Windows are short in the newborn months (often under an hour) and lengthen gradually across the first years.
Why do wake windows matter for naps?
A baby put down mid-window usually settles more easily; an overtired baby often fights sleep harder. Watching the window plus your baby's sleepy cues (zoning out, fussing, eye rubbing) makes nap timing far less of a guessing game.
Are wake windows exact rules?
No. They are typical ranges, not prescriptions. Babies vary, days vary, and windows usually lengthen from morning to evening. Treat the range as orientation and your baby's cues as the tiebreaker.
How much total sleep does my baby need?
Broad typical ranges are roughly 14 to 17 hours per 24 for newborns to 3 months, 12 to 16 hours for 4 to 12 months, and 11 to 14 hours for toddlers, naps included. Individual babies can fall outside these ranges and still be fine; your pediatrician is the right judge.
Growbaby watches the windows for you
The app tracks your baby's actual sleep, learns their rhythm, and nudges you when a nap window opens, then the adaptive soothing engine helps them settle into it. One subscription covers the whole family.
Sources
This tool is for general informational purposes only. It is not a medical device and does not provide medical advice, diagnosis or treatment. Sleep needs vary between healthy babies; the ranges here are typical, not targets. For any question about your or your baby's health, always consult a qualified healthcare provider.