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Wake Window Calculator
Tell it your baby's age and, if you like, what time they woke up. It shows the wake window that usually fits that age, when the next nap is roughly due, and how an example day could run — built from the same chart our readers use, with the first window a little shorter and the last one a little longer, the way most babies actually do it.
The same chart, on one printable page
The free Wake Window Cheat Sheet puts the 0–6 month chart and the sleepy cues on one printable page — the fridge-door version of this calculator.
Get the free cheat sheet →How this calculator works
The ranges come from our wake windows by age chart, which follows the total-sleep ranges in the American Academy of Sleep Medicine guidance endorsed by the AAP: 14–17 hours per 24 hours from birth to 3 months, 12–16 hours (including naps) at 4–12 months, and 11–14 hours (including naps) at 1–2 years. Wake windows themselves are a widely used parenting framework rather than a medical guideline — treat them as a starting point, and let your baby's sleepy cues have the final word.
Two honest adjustments are built in, because most babies do not run one flat window all day: the first window of the morning is shortened a little (about 15 minutes) and the last window before bed is stretched a little, each kept inside the age range. On one nap, toddlers flip the pattern — a long morning (about 5–6 hours before the nap) and a shorter stretch after it (about 4–5 hours) — so the example day flips with them. Example days use a typical nap length for the age and are labelled as examples: real babies nap longer and shorter, and that is normal.
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Wake windows by age — the full chart
| Age | Wake window | Naps per day | Total sleep per 24h | What it looks like |
|---|---|---|---|---|
| 0–4 weeks | 30–60 minutes | 4–6+ (often more in the first fortnight) | 14–17 hours | Feed, cuddle, back to sleep. Almost no "play" yet. |
| 1–2 months | 45 minutes–1.5 hours | 4–5 | 14–17 hours | First smiles appear inside these short windows. |
| 3 months | 1.25–2 hours | 3–4 | 14–17 hours | Windows start to feel predictable for the first time. |
| 4 months | 1.5–2.5 hours | 3–4 | 12–16 hours (including naps) | Sleep matures — this is the 4-month sleep regression change; windows jump. |
| 5 months | 2–2.5 hours | 3 | 12–16 hours (including naps) | Three solid naps is the classic pattern now. |
| 6 months | 2–3 hours | 2–3 | 12–16 hours (including naps) | The third nap starts getting refused — some babies start refusing it late in this stage; most drop it at 7–9 months. |
| 7–8 months | 2.5–3.5 hours | 2–3 | 12–16 hours (including naps) | Two naps settle in; first window is usually the shortest. |
| 9–10 months | 3–4 hours | 2 | 12–16 hours (including naps) | Crawling and pulling up burn real energy. |
| 11–12 months | 3–4 hours | 2 | 12–16 hours (including naps) | Fake-outs begin: a refused second nap isn't always a drop. |
| 13–15 months | 3–4.5 hours | 1–2 | 11–14 hours (including naps) | Two naps is still normal; one-nap days start alternating in. |
| 16–18 months | 4–6 hours | 1 | 11–14 hours (including naps) | The one-nap transition settles — often bumpy for a few weeks. |
| 19–24 months | 5–6 hours | 1 | 11–14 hours (including naps) | One long midday nap. On one nap the morning window is usually the longer one (about 5–6 hours before the nap, 4–5 hours after it) — the reverse of the baby pattern. |
Swipe sideways to see the full chart →
When the window doesn't fit
A window that is too long and one that is too short can look surprisingly similar — short naps, hard settling. The giveaway is your baby's behaviour around sleep: a wired second wind and a crash usually mean overtired, while a baby who plays happily in the crib for 20 minutes probably was not tired yet. Our guide walks through both sign lists and the 15-minute fix for each: too long or too short? How to tell.
Questions parents ask us
How do I work out my baby's wake window?
Find your baby's age band above — the wake window is the stretch they can comfortably stay awake between sleeps, including feeding, changing and the wind-down. If your baby woke at 7:00 and their window is about 2 hours, the next nap is roughly due at 9:00; start the nap routine a little before, and let sleepy cues make the final call.
Is the first wake window really the shortest?
For most babies, yes. Sleep pressure builds across the day, but the first window of the morning is usually the shortest and the last window before bed the longest. It is a tendency, not a law — some babies are the opposite, and toddlers on one nap usually flip the pattern entirely.
Are wake windows medical guidance?
No. Wake windows are a widely used parenting framework — no guideline body publishes an official wake-window table. What does come from medical guidance is the total amount of sleep: the ranges here follow the American Academy of Sleep Medicine figures endorsed by the AAP. For anything about your own baby's health or development, your pediatrician is the right call.
My baby's windows don't match the calculator — what now?
That is common, and usually fine. Work from your baby's cues and adjust one window at a time by 15 minutes for three days: shorter if they melt down before the window ends, longer if they play happily in the crib or take a long time to settle without seeming tired. The full sign lists are in our wake windows by age guide.
Want the whole plan, not just the chart?
Wake Windows Made Simple is the full 44-page kit: age-by-age charts up to 24 months, sample schedules for every stage, nap-transition playbooks and the troubleshooting pages for the hard weeks — printable, fridge-friendly, and written for 2 a.m. brains.
$5 at founding launch (regularly $30)
See Wake Windows Made Simple →Keep reading
Baby SleepNewborn Sleep Schedule: What the First 8 Weeks Really Look LikeNewborns sleep in short bursts, not schedules. A week-by-week look at weeks 1–8, with two sample days.
Baby SleepBaby Nap Schedule by Age (0–12 Months): Charts + Sample DaysHow many naps at every age, how long they last, and when the nap drops happen — with a sample day for each stage.
Baby SleepSleep Regression Ages: Every Regression From 4 Months to 2 YearsThe 4, 8–10 and 12-month, 18-month and 2-year regressions — what causes each one, how long it lasts, and what helps.
Baby Sleep4-Month Sleep Regression: Signs, How Long It Lasts & Survival TipsWhy sleep falls apart around four months, the signs it's the real thing, and the tips that actually help.
Baby SleepBaby Sleep Schedule by Age: Month-by-Month Charts (0–12)What a realistic day looks like at every age — wake times, naps and bedtime windows, month by month.
Swipe sideways for more →
Questions parents ask us
How do I work out my baby's wake window?
Find your baby's age band above — the wake window is the stretch they can comfortably stay awake between sleeps, including feeding, changing and the wind-down. If your baby woke at 7:00 and their window is about 2 hours, the next nap is roughly due at 9:00; start the nap routine a little before, and let sleepy cues make the final call.
Is the first wake window really the shortest?
For most babies, yes. Sleep pressure builds across the day, but the first window of the morning is usually the shortest and the last window before bed the longest. It is a tendency, not a law — some babies are the opposite, and toddlers on one nap usually flip the pattern entirely.
Are wake windows medical guidance?
No. Wake windows are a widely used parenting framework — no guideline body publishes an official wake-window table. What does come from medical guidance is the total amount of sleep: the ranges here follow the American Academy of Sleep Medicine figures endorsed by the AAP. For anything about your own baby's health or development, your pediatrician is the right call.
My baby's windows don't match the calculator — what now?
That is common, and usually fine. Work from your baby's cues and adjust one window at a time by 15 minutes for three days: shorter if they melt down before the window ends, longer if they play happily in the crib or take a long time to settle without seeming tired. The full sign lists are in our wake windows by age guide.
Want the whole plan, not just the chart?
Wake Windows Made Simple is the full 44-page kit: age-by-age charts up to 24 months, sample schedules for every stage, nap-transition playbooks and the troubleshooting pages for the hard weeks — printable, fridge-friendly, and written for 2 a.m. brains.
$5 at founding launch (regularly $30)
See Wake Windows Made Simple →Sources & further reading: AAP HealthyChildren — A Parent's Guide to Safe Sleep · KidsHealth (Nemours) — All About Sleep · Sleep Foundation — Newborn Wake Windows · CDC — About Sleep · HealthyChildren.org (AAP) — Healthy Sleep Habits: How Many Hours Does Your Child Need?