Wake Window Calculator

What time should my baby nap and go to bed?

Enter your baby's age and wake-up time to see when each nap should start and what time bedtime falls, from newborn to 12 months.

3months
012 months

Today's sleep schedule

Wake up
7:00 am
Nap 1
after 1h25 awake
8:25 am – 9:40 am
Nap 2
after 1h40 awake
11:20 am – 12:40 pm
Nap 3
after 1h50 awake
2:30 pm – 3:50 pm
Bedtime
after 2h10 awake
6:00 pm
Wake windows
1h25–2h05
Naps
3
Sleep in 24h
12–15h

A starting point, not a rule: every baby has their own rhythm, and 15–20 minutes either way is normal. If a nap runs short, count the next wake window from when your baby actually woke up, and watch for tired cues (yawning, staring, fussiness).

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Baby routine by age

Also helpful:

What Is a Wake Window?

A wake window is how long your baby can comfortably stay awake between one sleep and the next. It is short in the newborn weeks (around 35–55 minutes) and grows through the first year, to about 3½–5 hours by 12 months. Catching your baby at the end of the window, before they get overtired, is what makes naps and bedtime easier.

How the Calculator Builds Your Baby's Day

The calculator starts from the time your baby woke up and walks through the day with the same rules the BabyLingo app uses:

  • Wake windows grow across the day: the first one after the morning wake-up is the shortest, and the one before bed is the longest.
  • Typical nap length for the age: each nap uses the average duration for your baby's age.
  • No naps after 6 pm: once evening arrives, the next sleep is bedtime.
  • Bedtime between 6 pm and 8:30 pm: the window most babies settle into in the first year.

The numbers come from the wake-window curve used in the BabyLingo app, with total-sleep guidance from the AAP. For the full chart, with naps per day and total sleep by age, see wake windows by age.

When the Day Doesn't Go to Plan

Short naps, a car ride, a doctor's appointment: real days drift. The simplest fix is to restart the count. Note when your baby woke from the last sleep and offer the next one after a wake window for their age. A short last nap usually means an earlier bedtime, not a later one.

Frequently Asked Questions

What is a wake window for a baby?
A wake window is how long your baby stays awake between two sleeps. It starts at around 35–55 minutes for newborns and grows to about 3½–5 hours by 12 months. Offering sleep at the end of the window helps avoid an overtired baby.
What time should my baby go to bed?
Most babies in the first year do well with a bedtime between 6 pm and 8:30 pm. The exact time depends on when your baby woke up and how the naps went: a day with short naps usually calls for an earlier bedtime.
What if my baby's nap is shorter than the calculator shows?
Count the next wake window from when your baby actually woke up. The calculator assumes a typical nap length for the age, so a short nap moves everything after it a little earlier.
How many naps does my baby need?
It drops through the first year: around 4–6 short naps for newborns, 3–4 at 2–3 months, about 3 at 4–6 months, 2 from around 8–9 months, and many move to a single nap between 12 and 18 months. The wake windows by age chart shows the full range for each age.
Is the schedule the same for every baby?
No. These are averages for the age, a starting point to adjust. Your baby's tired cues matter as much as the clock, and 15–20 minutes earlier or later is completely normal.

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A routine that adapts to your baby’s real naps, a weekly development summary and the skills coming up next.

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