Wake window calculator
Enter your baby's age and when they woke up. You'll see when the next nap is likely.
Enter your baby’s age to see their wake window.
Ranges, not rules. The first window of the day is usually the shortest and the last one before bed the longest, and if your baby looks tired sooner, go with that. The NHS does not publish wake windows, so these come from paediatric sleep practice. Your health visitor knows your baby best.
Wake windows by age
The ranges the calculator uses, from birth to 24 months. Treat them as a starting point, as your baby may sit a little either side.
| Age | Awake for | Naps a day |
|---|---|---|
| Weeks 0–2 | 30–45 minutes | 4–6+ (on and off) |
| Weeks 3–4 | 40–60 minutes | 4–6+ (on and off) |
| Weeks 5–6 | 45–75 minutes | 4–5 |
| Weeks 7–8 | 60–90 minutes | 4–5 |
| Weeks 9–10 | 60–90 minutes | 4–5 |
| Weeks 11–12 | 75–90 minutes | 3–5 |
| 3–4 months | 75–120 minutes | 3–5 |
| 5–6 months | 2–2.5 hours | 3 |
| 7–9 months | 2.5–3 hours | 2–3 |
| 10–12 months | 3–4 hours | 2 |
| 13–15 months | 3.5–4.5 hours | 1–2 |
| 16–24 months | 4–6 hours | 1 |
Common questions
What is a wake window?
It's how long your baby is awake between sleeps, from the moment they open their eyes to the moment they go back down. That includes the feed, the nappy change and the wind-down, not just the time spent playing.
How does the calculator work?
It adds the typical wake window for your baby's age to the time they woke up. You get a range because babies don't run to a clock. The first window of the day is usually the shortest and the last one before bed the longest. Read the full guide to wake windows.
What if my baby seems tired sooner?
Go with your baby. Staring into the middle distance, losing interest in toys, rubbing their eyes or turning their face away are early tired signs, and they matter more than the clock.
Does the NHS publish wake windows?
No. These ranges come from paediatric sleep practice, not nhs.uk. NHS guidance covers safe sleep and following your baby's cues, and your health visitor can help with your own baby's routine.
My baby was born early. Which age should I use?
Try your baby's corrected age, counted from their due date. It's the age NHS teams use when monitoring a premature baby's development. We couldn't find NHS or Bliss guidance on wake windows for babies born early, so ask your health visitor or neonatal team if you're unsure. What corrected age means (University Hospital Southampton).
Related guides
CubTrack is a baby tracker, not a medical service. This calculator gives general information, and your midwife, health visitor or GP knows your baby and should guide decisions about their care.