Baby wake window calculator
Know when the next nap is due
Enter your baby's age and last wake-up to see the likely nap window.
Wake windows by age
| Age | Wake window | Naps | Total sleep |
|---|---|---|---|
| Newborn (0–1 month) | 30 min – 1h | 4–6 or more | 14–17 hours |
| 1–2 months | 45 min – 1h 30m | 4–5 | 14–17 hours |
| 2–3 months | 1h – 1h 30m | 4–5 | 14–17 hours |
| 3–5 months | 1h 30m – 2h 30m | 3–4 | 12–16 hours |
| 5–7 months | 2h – 3h | 2–3 | 12–16 hours |
| 7–10 months | 2h 30m – 3h 30m | 2–3 | 12–16 hours |
| 10–12 months | 3h – 4h | 2 | 12–16 hours |
| 12–18 months | 3h – 4h | 1–2 | 11–14 hours |
| 18–24 months | 4h – 6h | 1 | 11–14 hours |
Sources and notes
- Total sleep: National Sleep Foundation (2015) for 0–3 months; AASM (2016) for 4 months and older.
- Wake windows: ranges where two commonly cited guides overlap: Cradlewise (to 12 months) and The Baby Sleep Site. These are not medical guidelines and the sources differ.
- This tool does not give advice on sleep training, feeding schedules or medication. For concerns about your baby's sleep, talk to your pediatrician.
Questions
What is a wake window?
The stretch of time your baby is comfortably awake between sleeps. It grows as your baby gets older.
Are these numbers exact?
No. There is no official guideline for wake windows. The ranges here are commonly reported figures and sources disagree, so your baby may need more or less awake time.
What if my baby seems tired before the window opens?
Follow your baby. Yawning, rubbing eyes, staring off or fussing are cues that sleep is due, even if the window has not opened yet.
Baby wake window calculator: time naps by age
A wake window is the length of time a baby can comfortably stay awake between sleeps. Put a baby down before the window opens and they may not be tired enough; leave it too late and they can become overtired, which often makes sleep harder, not easier. This baby wake window calculator takes your baby's age and the time they last woke up and shows the likely nap window as a time range, with a live countdown.
Parents search for "baby wake windows by age", "how long should my baby be awake" and "newborn wake window" because the guidance in books and apps can feel confusing. The tool puts the ranges in one place and does the arithmetic for you.
How to use the calculator
Choose your baby's age and enter the time they woke up from their last sleep. The calculator adds the typical wake window for that age and shows when to start the wind-down, for example "nap window 10:15 AM to 11:00 AM". A countdown shows how long is left until the window opens. Use it as a guide and put your baby's own signals first: yawning, staring, rubbing eyes and fussing all matter more than any chart.
Typical wake windows by age
There is no official medical guideline for wake windows. The ranges commonly reported by sleep consultants and parenting sources are approximate: newborns often manage only 45 to 90 minutes, babies of 3 to 4 months around 1 to 2 hours, 6 to 8 months around 2 to 3 hours, 9 to 12 months around 2.5 to 4 hours and toddlers 4 to 6 hours. Babies differ a lot, and a window can be shorter after a poor sleep and longer after a good one. The tool uses conservative bands where reputable sources overlap.
Signs your baby is tired
Early tired signs include going quiet, a glazed look, losing interest in toys, yawning and rubbing eyes or ears. Late signs include arching, crying and a sudden burst of energy that looks like a second wind. If you see late signs, start the nap routine sooner next time. The wake window is a starting point to help you spot the signs earlier.
Wake windows and total sleep
Total sleep needs fall as babies grow: roughly 14 to 17 hours a day for newborns, 12 to 16 for babies of 4 to 12 months and 11 to 14 for toddlers aged 1 to 2 years, according to the American Academy of Sleep Medicine. See the sleep needs by age chart, and plan a whole day with the baby nap schedule tool.
Safe sleep always comes first
Whatever the schedule, follow safe sleep guidance from your health provider: place your baby on their back, on a firm, flat sleep surface with no loose bedding, pillows or soft toys, and keep the sleep space in the room with you for at least the first six months. Do not use a car seat or sofa for regular sleep. Our tool provides general information and does not replace advice from your doctor or health visitor.
When schedules wobble
Growth spurts, teething, illness and travel can all disrupt naps. A rough patch around 4, 8 to 10, 12 or 18 months is often described as a sleep regression. Use the sleep regression checker to see whether your baby's age fits a commonly reported period. If you are sharing night duty, the new parent night planner helps split the night so each person gets a longer block of rest.
Worked example
A 5-month-old wakes at 7:00 AM. A common wake window for this age is about 1.5 to 2.5 hours, so the first nap window runs from 8:30 AM to 9:30 AM. If the baby woke from that nap at 10:15, the next window opens around 11:45. The calculator does this for each nap and counts down on screen. Watch your baby as you approach the end of the window and start the routine when you see tired signs.
Short wake windows after a short nap
After a short nap, a baby may be tired sooner. If the nap lasted 30 minutes and your baby seems unsettled, try the lower end of the window. Likewise, after a long, restful nap, the upper end often works. Keep a rough note for a few days and you will see your baby's pattern.
Wake windows and bedtime
The last wake window of the day is often the longest because sleep pressure builds towards night. A very early bedtime can lead to early waking and a very late one to an overtired baby, so aim for a window that is long enough for tiredness but not so long that crying begins. The baby nap schedule tool works out a suggested bedtime.
Wake windows for toddlers and the move to one nap
Between 12 and 18 months, many toddlers move from two naps to one. The wake window before the single nap grows to about five to six hours, with a lunchtime nap of one to two hours and bedtime about five hours later. During the change, which can last weeks, you may alternate between one and two naps depending on the day. Use the tool as a guide and keep bedtime earlier on days with a missed or short nap.
Wake windows and feeding
Young babies often feed at the start or end of a wake window. If your baby feeds as part of the sleep routine, the window is counted from when they wake, not from when the feed ends. Some families aim to feed after waking so that babies do not rely on feeding to fall asleep. This is a personal choice, and your health provider can advise on what suits your baby, especially if you have concerns about weight or feeding.
Frequently asked questions
How long should a 3-month-old stay awake?
Commonly about 1 to 2 hours between sleeps. Watch your baby for tired signs as well as the clock.
What happens if I miss the wake window?
The baby may become overtired and find it harder to settle. It is not harmful, and you can shorten the next window to catch up.
Are wake windows backed by science?
They are practical rules of thumb used by sleep consultants. The tool uses typical ranges, but babies vary.
Does the countdown work offline?
Yes. Once the page has loaded it works without internet.
Should I wake a baby to keep to the schedule?
For young newborns, ask your health provider about feeding and waking. For older babies, a gentle flexible approach is usually fine.
Guides for this tool
General information only. This tool gives general sleep information and is not a substitute for medical advice. If you're worried about your sleep or your child's, talk to a doctor or pediatrician.