Free baby sleep tools
⏱️ Wake window calculator
A wake window is the time your baby is awake between one sleep and the next. Get it close and babies tend to settle more easily. Enter an age to see the typical range.
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Wake windows by age
| Age | Wake window | Naps a day |
|---|---|---|
| Newborn (0 to 6 weeks) | 30m to 1h 30m | 6 |
| 2 months | 45m to 1h 30m | 4 |
| 3 months | 1h to 1h 45m | 4 |
| 4 months | 1h 15m to 2h | 4 |
| 5 months | 1h 41m to 2h 35m | 3 |
| 6 months | 2h to 3h | 3 |
| 7 months | 2h 13m to 3h 13m | 3 |
| 8 months | 2h 30m to 3h 30m | 2 |
| 9 months | 2h 45m to 3h 45m | 2 |
| 10 months | 3h to 4h | 2 |
| 11 months | 3h to 4h | 2 |
| 12 months | 3h 8m to 4h | 2 |
| 14 months | 3h 15m to 4h | 2 |
| 16 months | 4h to 4h 52m | 1 |
| 18 months | 5h to 6h | 1 |
| 24 months | 5h to 6h | 1 |
| 30 months | 5h to 6h | 1 |
| 36 months | 5h 32m to 7h 4m | 1 |
What a wake window is
Sleep pressure builds the longer a baby is awake. Put them down too early and they are not tired enough to drift off. Leave it too long and they can become overtired, which often makes settling harder and nights more broken. The wake window is the sweet spot in between.
Why the ranges are ranges
These numbers are a starting point, not a rule. Some babies sit happily at the top of the range and some need a little less. Sleepy cues like a glazed stare, rubbing eyes, pulling ears or turning away from play are just as useful as the clock.
How OBubba personalises it
The table is based on published age guidance. Inside the app, OBubba watches the wake windows your baby actually does well on and gradually moves its predictions towards them, so the suggestion becomes about your baby rather than the average one.
Let OBubba do this for you
This chart is the average baby. OBubba learns yours.
OBubba learns your baby’s own wake windows from what you log, predicts the next nap and bedtime, and spots over 30 common sleep disruptions with a gentle plan for each. Free to download.
Questions parents ask
Frequently asked questions
How long should a newborn be awake?
Most newborns manage about 30 to 90 minutes awake, and in the first couple of weeks it is often closer to 45 to 60 minutes including the feed and a nappy change.
What is the wake window for a 6 month old?
Around 2 to 3 hours for most 6 month olds, usually across three naps. The first window of the day tends to be the shortest.
Should the wake window be the same all day?
Usually not. Windows tend to get longer as the day goes on, so the stretch before bedtime is often the longest one.
My baby is premature. Which age should I use?
If your baby was born more than about three weeks early, use their corrected age (age from the due date) for sleep expectations, up to around two years.
Related guides
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Sleep regression checkerWhich common sleep shake-ups line up with your baby’s age, and what helps.
Nap transition checkerIs your baby ready to drop a nap? Four signs to check.Sources
OBubba tools give general, age-based information. They are not medical advice and do not diagnose anything. Every baby is different. If you are worried about your baby, speak to your health visitor, midwife, GP or call NHS 111 (or your local equivalent).