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How long can your baby stay awake?

A wake window is the stretch between waking up and being ready to sleep again. Keep it roughly right and falling asleep gets easier - too long and you get an overtired baby who fights the nap. Enter a date of birth below.

Optional - add it to get the time of the next nap.

Predictions then use corrected age, the way a paediatrician would. The age shown stays the real one.

Fill in a date of birth and the numbers appear here.

Wake windows by age

The same table BabyLedger uses - a starting point, not a schedule. Real babies vary far more than a single number suggests: at 0-2 months the normal range for total daily sleep runs from about 9 to 20 hours, and it stays hours wide through the second year. Your baby’s sleepy cues beat the table.

AgeWake windowTypical
0-2 weeks35 min – 1 h45 min
2-4 weeks45 min – 1 h 15 min1 h
1-2 months1 h – 1 h 30 min1 h 15 min
2-3 months1 h 15 min – 1 h 45 min1 h 30 min
3-4 months1 h 30 min – 2 h1 h 45 min
4-6 months1 h 45 min – 2 h 30 min2 h
6-9 months2 h – 3 h2 h 30 min
9-12 months2 h 30 min – 4 h3 h
12-18 months3 h 30 min – 5 h4 h
18-24 months4 h 30 min – 6 h5 h
2-3 years5 h – 7 h6 h

The 2-3 years row only holds while your child still naps. Once the nap goes, the day becomes one long stretch of awake time and a consistent bedtime matters more than any window.

This calculator is general information, not medical advice. It is no substitute for a paediatrician or a certified sleep consultant - if you have questions about your child’s sleep or health, ask one. Disclaimer

The three nap transitions

Most of the confusion about wake windows comes from the weeks around a nap transition. The old rhythm stops working, the new one has not settled, and the table is between two rows.

  1. 4-6 months

    Several naps become two

    Night sleep separates from daytime sleep and the scattered newborn naps consolidate. By around 9 months two naps of roughly an hour and a half are the norm.

  2. 12-18 months

    Two naps become one

    The morning nap fades first. The single midday nap that replaces it comes with a much longer stretch of awake time before bedtime.

  3. 2-4 years

    The last nap goes

    The widest spread of them all - some children stop before their second birthday, others still nap at school age. After it, a steady bedtime does the work the nap used to.

What it looks like from the outside: naps suddenly get short, one gets refused outright, or your child starts waking earlier. It usually settles within a few weeks. Through a transition the wake windows run longer than the age row suggests - that is the point of a transition, not a sign anything is wrong.

Stop doing this maths in your head.

BabyLedger keeps the countdown on the home screen and, with Plus, learns your own baby’s rhythm instead of reading it off this table.

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