Wake Window Calculator
Enter your baby's age in months and the time they wake up, and this calculator returns every wake window, the nap times in between, and a sensible bedtime for the night. It covers newborns through 36 months using typical AAP, CDC and National Sleep Foundation ranges.
Not medical advice. For emergencies, call your local emergency number.
Your day —
Every child is different — these are typical ranges, not targets. Watch sleepy cues and shift times by 15–30 minutes to fit your family.
Wake windows by age (0–36 months)
| Age | Wake window | Naps/day | Nap length | Total sleep (24 h) |
|---|---|---|---|---|
| 0 months (newborn) | 45–90 min | 3–4 | 1–1.5 h | 14–17 h |
| 1 month | 60–90 min | 4 | 1–1.5 h | 14–16 h |
| 2 months | 60–90 min | 3–4 | 1–1.5 h | 14–15 h |
| 3 months | 1.25–2 h | 3 | 1–1.5 h | 14–15 h |
| 4 months | 1.5–2 h | 3 | 1–1.5 h | 12–15 h |
| 5 months | 2–2.5 h | 2–3 | 1–1.5 h | 12–14 h |
| 6 months | 2.5–3 h | 2 | 1–1.5 h | 12–14 h |
| 7 months | 2.5–3 h | 2 | 1–1.5 h | 12–14 h |
| 8 months | 2.5–3 h | 2 | 1–1.5 h | 12–14 h |
| 9 months | 3–3.25 h | 2 | 1–1.5 h | 12–14 h |
| 10 months | 3–3.5 h | 2 | 1–1.5 h | 12–14 h |
| 11 months | 3–3.5 h | 2 | 1–1.5 h | 12–14 h |
| 12 months | 3–3.5 h | 2 | 1–1.5 h | 12–14 h |
| 13 months | 3.5–4 h | 2 | 1–1.5 h | 11–14 h |
| 14 months | 3.5–4 h | 1–2 | 1–1.5 h | 11–14 h |
| 15 months | 4–4.5 h | 1 | 1.5–2 h | 11–14 h |
| 16 months | 4–4.5 h | 1 | 1.5–2 h | 11–14 h |
| 17 months | 4–4.5 h | 1 | 1.5–2 h | 11–14 h |
| 18 months | 4.5–5 h | 1 | 1.5–2 h | 11–14 h |
| 19 months | 4.5–5 h | 1 | 1.5–2 h | 11–14 h |
| 20 months | 4.5–5 h | 1 | 1.5–2 h | 11–14 h |
| 21 months | 4.5–5 h | 1 | 1.5–2 h | 11–14 h |
| 22 months | 5–5.5 h | 1 | 1.5–2 h | 11–14 h |
| 23 months | 5–5.5 h | 1 | 1.5–2 h | 11–14 h |
| 24 months (2 years) | 5–6 h | 1 | 1.5–2 h | 11–14 h |
| 25 months | 5–6 h | 1 | 1.5–2 h | 11–14 h |
| 26 months | 5–6 h | 1 | 1.5–2 h | 11–14 h |
| 27 months | 5–6 h | 1 | 1.5–2 h | 11–14 h |
| 28 months | 5–6 h | 1 | 1.5–2 h | 11–14 h |
| 29 months | 5–6 h | 1 | 1.5–2 h | 11–14 h |
| 30 months | 5–6 h | 1 | 1.5–2 h | 11–14 h |
| 31 months | 5–6 h | 1 | 1–1.5 h | 10–13 h |
| 32 months | 5–6 h | 1 | 1–1.5 h | 10–13 h |
| 33 months | 5–6 h | 1 | 1–1.5 h | 10–13 h |
| 34 months | 5–6 h | 1 | 1–1.5 h | 10–13 h |
| 35 months | 5–6 h | 1 | 1–1.5 h | 10–13 h |
| 36 months (3 years) | 5–6 h | 1 | 1–1.5 h | 10–13 h |
Ranges follow typical guidance: the American Academy of Pediatrics (AAP) and CDC recommend 12–16 hours of sleep for babies aged 4–12 months and 11–14 hours for toddlers aged 1–2 years, and the National Sleep Foundation (NSF) lists 10–13 hours for three-year-olds.
Frequently asked questions
- How do I use the wake window calculator?
- Set your child's age in months and their usual wake-up time. The calculator shows every wake window for the day, the nap start and end times, and the bedtime that follows the final wake window.
- What is a wake window?
- A wake window is the stretch of time a baby can comfortably stay awake before their next sleep. It lengthens with age: roughly 45–90 minutes for a newborn and 5–6 hours by age three.
- What if my baby's wake windows don't match the chart?
- Every child is different. Treat these as starting points, watch sleepy cues, and shift times by 15–30 minutes to fit your family. Ask your pediatrician if your baby is struggling with sleep.
- Is this medical advice?
- No. The calculator shares typical ranges described by the AAP, CDC and National Sleep Foundation for planning purposes only. It is not medical advice — talk to your pediatrician about your child's sleep.