A wake window is the stretch of time your baby is awake between sleeps. Counting from the last wake-up gives you something to work with on a day when the nap schedule has already fallen apart.
This category brings together our guides to wake windows, the 3 to 2 and 2 to 1 nap transitions, the best bedtime by age, and how to build a bedtime routine, plus our general tips to help your baby sleep.
Where The Numbers Come From
Sleep pressure builds while your baby is awake and clears while they sleep. Researchers think it may build faster in younger children, which could help explain why babies nap more often, but the evidence for that is preliminary: it comes from one small study of eight children aged 2 to 5.
The month-by-month charts are a different matter. NHS national guidance on baby sleep does not use the term "wake window" at all, and the age ranges you see online come from sleep-coaching practice rather than clinical research. No study sets a correct wake window for an individual baby. Treat every range as a place to start rather than a target to hit. Our guide to what wake windows are sets out what the guidance does and does not say.
What Holds True Across Ages
When bedtime suddenly gets harder, the last nap or the final wake window is often the cause, though illness, teething and new skills can unsettle bedtime too. Check the timing of the day before you rebuild the sequence.
Watch your baby as well as the clock. Staring into space, going quiet, rubbing eyes or ears, and losing interest in play tell you where your baby sits inside today's range. A baby who slept badly overnight or had a short first nap will need the shorter end of it.
Both ends cause trouble. Too little awake time and your baby may not be tired enough to settle. Too much and settling usually gets harder, not easier, with more crying, shorter naps and false starts in the evening.
If naps are changing, read about the 3 to 2 nap transition and when babies drop to one nap. If bedtime is the part that keeps unravelling, start with the best bedtime for your baby by age and how to establish a bedtime routine.
