Wake window calculator
A wake window is how long a baby can comfortably stay awake between sleeps. It gets longer as they grow, which is why the nap that worked last month stops working.
Work out your wake window
Wake windows by age
| Age | Awake between sleeps | Sleep per 24 hours |
|---|---|---|
| 0–3 months | 1 h 30 min | 14–17 h |
| 3–6 months | 2 h | 12–16 h |
| 6–9 months | 3 h | 12–16 h |
| 9–12 months | 4 h | 12–16 h |
| 12–18 months | 5 h | 11–14 h |
| 18–24 months | 6 h | 11–14 h |
| 24–36 months | 8 h | 11–14 h |
| 36–48 months | — | 10–13 h |
| 48–60 months | — | 10–13 h |
| 60+ months | — | 9–12 h |
Sleep per 24 hours includes daytime naps. Ranges follow the American Academy of Sleep Medicine recommendations endorsed by the AAP. Every baby sits somewhere in the range rather than on a single number.
Questions parents ask
What is a wake window?
The stretch of time a baby is awake between one sleep ending and the next beginning. Keeping to a length that suits their age usually makes falling asleep easier, because an overtired baby fights sleep rather than sinking into it.
My baby does not fit the table. Is something wrong?
No. The figures are a starting point, not a target. Babies vary widely, and the window that works for yours can sit either side of the range for their age. The pattern over a week tells you more than any single nap.
When do wake windows stop mattering?
Around three years, when naps end and there is a single sleep period a day. From then on the useful question is total sleep and a consistent bedtime rather than the gap between sleeps.
Can the app work this out from my own baby instead?
Yes, and that is the difference. Pixy starts from the same age-based figures, then replaces them with the median of your own baby's logged wake windows once there is enough history. Sleep predictions are free and stay free.
Let it learn your baby instead
This page gives you the number for your age band. Pixy gives you the number for your child, from their own sleep history, and tells you before the window closes.
Pixy is a tracking tool, not a medical device, and this page is general information rather than advice. Speak to a doctor or health visitor about your child specifically.