Sleepabee

Wake windows by age

5 min read

How long a baby can comfortably stay awake between sleeps, why it grows every few weeks, and how to use it without watching the clock.

A wake window is the stretch of time your baby is awake between two sleeps — from waking up to falling asleep for the next nap, or for the night. It is one of the most useful ideas in baby sleep, and one of the most misunderstood.

Why wake windows matter

Babies build up sleep pressure while they are awake. Put a baby down too soon and they may not be tired enough to fall asleep or to stay asleep. Keep them up too long and they can become overtired: fussier, harder to settle, and more likely to wake early from a nap or during the night.

The right wake window is not a fixed number. It grows quickly in the first year — sleep experts suggest looking at it again every month — and it differs a little from child to child.

Typical wake windows by age

These ranges are the ones Sleepabee uses to plan a day. They come from the wake-window guidance of baby-sleep specialists; there is no medical consensus figure for wake windows, so treat them as a starting point.

AgeTypical wake windowUsual number of naps
0–2 months50–75 minutes4–5
2–3 months70–90 minutes4–5
3–4 months1 h 20 min – 1 h 45 min3–4
4–5 months1 h 30 min – 2 h3–4
5–6 months2 h – 2 h 15 min (the first window of the day can be as short as 1 h 30 min)3–4
6–8 months2 h 15 min – 3 h2–3
8–9 months2 h 30 min – 3 h 30 min2–3
9–12 months3 h – 3 h 45 min2
12–15 months3 h 15 min – 5 h1–2
15–18 months3 h 15 min – 5 h 15 min1–2
18–24 monthsabout 5 hours1

The wide ranges after the first birthday are not a mistake: a toddler on two naps has much shorter windows (around 3–4 hours) than one who has moved to a single nap (around 5 hours).

How to use them

  • Start with the shorter end in the morning. The first wake window of the day is usually the shortest, and the one before bedtime the longest.
  • Watch your child, not only the clock. Yawning, rubbing eyes, staring into the distance, turning away from people or toys, and getting fussy are common signs of a tired baby. Some babies show very few cues, which is where a typical range helps.
  • A range, not a rule. A baby at the start of a range will often need the shorter end; a baby about to move into the next range, the longer end.
  • Expect change. Wake windows stretch noticeably around nap transitions. If naps suddenly get short or bedtime turns into a battle, the window may simply have grown.

When the range does not seem to fit

If your baby is consistently happy on windows well outside these ranges, sleeps enough in total, and is growing well, that is fine — these numbers describe most babies, not every baby. If short naps, very early mornings or long bedtime battles keep happening, try moving the wake window a little in one direction for a few days before changing anything else.

When to talk to a doctor

Talk to your doctor or health visitor soon if your child:

  • snores often, seems to struggle to breathe at night, or is very sleepy during the day;
  • is not gaining weight as expected, or has lost their appetite;
  • has sleep problems you are finding hard to manage.

If you are worried and not sure what to do, it is always fine to ask.

If your baby is under 3 months old with a temperature of 38 °C (100.4 °F) or higher, or 3–6 months old with 39 °C (102.2 °F) or higher, call your doctor straight away. If you cannot reach a doctor, call your local emergency number.

Call your local emergency number now if your baby:

  • stops breathing for more than 20 seconds;
  • is breathing very fast or with great effort — grunting, or sucking their tummy in with each breath;
  • has blue, grey, pale or blotchy skin, lips or tongue;
  • is very hard to wake, or will not wake up;
  • is floppy, or is not feeding;
  • has a seizure (fit), or a rash that does not fade when you press a glass against it.

Sources

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