The daily routine of a 4-month-old

Four months is the month when two things happen at once: the rhythm simplifies — from four naps to three — and the architecture of sleep shifts to an adult one.

The second often explains why the first goes badly. Your baby surfaces more between two cycles, including mid-nap, and the days can feel more chaotic than at three months even though the rhythm is in fact getting organised.

The day below shows what a day that runs smoothly looks like at this age. On the days it does not run smoothly, only one variable is worth adjusting: the awake window.

Their typical day

Wake-up at

07:00Morning wake-up
awake 2 h
09:00Nap 1 · until about 10:45 (1 h 45)
awake 2 h 15
13:00Nap 2 · until about 14:25 (1 h 25)
awake 2 h 30
16:55Nap 3 · until about 18:00 (1 h 05)
awake 2 h 45
20:45Bedtime

Naps: 3
Daytime sleep: 4 h 15
Awake windows: 1 h 45 – 2 h 15
Night: 10 h 15

Calculated from the figures for this age. These are starting points, not instructions: your child’s tiredness signals come before the clock.

The awake windows at this age

First window, on waking: 2 h
Between two naps: 2 h 15 – 2 h 30
Last window, before bedtime: 2 h 45

The first window of the day is the shortest, the last the longest. That holds at every age, and it is what stops you putting down a child who has not built enough sleep pressure yet.

If your baby wakes earlier or later

The whole day shifts. What matters is the gaps between the moments, not the times themselves.

Wake-up at 06:30

Nap 108:30 – 10:15
Nap 212:30 – 13:55
Nap 316:25 – 17:30
Bedtime20:15

Wake-up at 07:30

Nap 109:25 – 11:10
Nap 213:20 – 14:45
Nap 317:05 – 18:10
Bedtime20:45

The key point at this age

The fourth nap goes, and bedtime moves earlier

The move from four naps to three almost always happens between three and five months, and it has a direct consequence few parents anticipate: the day loses about an hour of daytime sleep. That sleep has to be made up somewhere, and the only place available is the start of the night. In practice, on three-nap days move bedtime twenty to thirty minutes earlier.

The page for this age

When the day goes off the rails

They have been waking every hour for a few nights

Look at the date before you look at the naps. Around four months the architecture of sleep shifts to an adult one, and waking between two cycles becomes far more complete. The daily rhythm is not the cause, and changing it now would mean altering the one thing that was still working.

The naps have dropped to thirty minutes

Same cause: your baby now surfaces much higher between two cycles, including mid-nap. Total darkness and an adjusted awake window help. Linking two cycles usually arrives between five and seven months — there is nothing to force before then.

They fall asleep at 6 p.m. and wake at 5 a.m.

That is the sign of a day that ended too early, often after a lost nap. Putting down a baby in heavy sleep debt produces a night that starts early and finishes early. The next day, do not shift bedtime all at once: go back to the awake windows for their age and let the night settle over two or three days.

What changes before and after

By age	Naps	Daytime sleep	Bedtime
3 months	4	5 h 15	20:45
4 months	3	4 h 15	20:45
5 months	3	3 h 45	20:30

The questions of this age

How long are awake windows at 4 months?

Between 1 h 40 and 2 h 30 depending on the time of day. The first window of the morning is the shortest, the one before bedtime the longest — count about thirty minutes more.

My 4-month-old only takes 30-minute naps, what can I do?

That is one complete cycle stopping instead of linking to the next, and it is very common at this age. Total darkness and a properly adjusted awake window help more than anything else. Linking two cycles usually arrives between five and seven months.

Do you need fixed times at 4 months?

No, and trying to pin them down now mostly creates frustration. What settles first is the order of the day and the length of the awake windows; the clock times follow on their own around six months.

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