Wake window calculator
Enter your baby's age and the time they last woke up to see the typical awake window for that age and when the next nap is likely to be due.
Next sleep window
Typical awake time (3 to 4 months)
1 h 15 min to 2 h
Aim to start the next nap
08:15 to 09:00
Expect 3 to 4 naps and about 12 to 16 h of sleep in 24 hours at this age.
Wake windows by age
| Age | Wake window | Naps | Total sleep |
|---|---|---|---|
| 0 to 6 weeks | 45 min to 1 h | 4 to 6 naps | 14 to 17 h |
| 6 weeks to 3 months | 1 h to 1 h 30 min | 4 to 5 naps | 14 to 16 h |
| 3 to 4 months | 1 h 15 min to 2 h | 3 to 4 naps | 12 to 16 h |
| 4 to 6 months | 1 h 45 min to 2 h 30 min | 3 naps | 12 to 16 h |
| 6 to 9 months | 2 h 30 min to 3 h | 2 to 3 naps | 12 to 15 h |
| 9 to 12 months | 3 h to 4 h | 2 naps | 12 to 15 h |
| 12 to 18 months | 3 h 30 min to 5 h | 1 to 2 naps | 11 to 14 h |
| 18 to 24 months | 5 h to 6 h | 1 nap | 11 to 14 h |
How to use the window
Start watching for sleepy signs at the lower end of the range rather than waiting for the upper end. Staring into space, losing interest in play, jerky movements and ear pulling usually arrive before yawning. A baby put down inside the window falls asleep faster and tends to nap longer.
The chart is a starting point, not a rule. Two weeks of your own sleep logs will tell you your baby's real average, which is the number worth planning around. More on that in baby sleep patterns by age. Background reading from the Sleep Foundation. This tool is general information, not medical advice.
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Frequently asked questions
What is a wake window?
The time a baby can comfortably stay awake between sleeps, measured from the moment they wake to the moment they fall asleep again. It lengthens steadily through the first year.
What are typical wake windows by age?
About 45 to 60 minutes for newborns, 1 to 2 hours at 3 to 4 months, 2 to 3 hours at 6 months, 3 to 4 hours at 9 to 12 months and 4 to 6 hours by 18 months.
What happens if a wake window is too long?
Overtired babies usually take longer to fall asleep, wake more often between cycles and nap shorter. Fussiness, staring, ear pulling and jerky movements often appear before the yawn.
Are wake windows the same for every baby?
No. Charts give a range, and your own logs give the answer. After two weeks of tracking, the average awake time before a good nap is more reliable than any chart.