Baby wake windows calculator: how long between sleeps
Enter your baby's birth date and get the typical wake window for today, plus how many naps usually fit in a day. It runs in your browser, the date goes nowhere, and no signup is needed.
Your baby's wake window today
A wake window is the stretch between the end of one sleep and the start of the next.
Wake windows by age: the full table
These are the same ranges the LEELALU app tracker uses to guess the next sleepy window, so this page and the app never disagree. They are gentle guesses, not rules.
| Age | Typical wake window | Naps per day |
|---|
How to use these ranges
Treat the range as a frame, and your baby's cues as the picture. Toward the end of a wake window, watch for the early sleepy signs: a glazed stare, slower movements, turning away from faces, a first yawn. Starting the wind-down on the early side of the range is usually easier than catching up with an overtired baby.
For context on why the windows start so short: newborns sleep about 16 to 17 hours across a full day, often in stretches of only 1 to 2 hours, so short awake stretches are simply the arithmetic of that much sleep (AAP HealthyChildren, sourced below).
- Shorter than the range and happy? Some babies simply need less. That can be normal.
- Fighting sleep at the end of the range? Try moving the wind-down 10 to 15 minutes earlier for a few days.
- Every baby varies, and the same baby varies week to week. Growth spurts, illness, and new skills all shuffle the schedule for a while.
Born early? Count from the due date
For babies born before 37 weeks, sleep development tends to follow the corrected age (age counted from the due date) rather than the birth date. That is why the calculator has the optional "weeks early" field: it shifts the table to your baby's corrected age.
Sources
The wake window ranges above are the exact table inside the LEELALU app: our deliberately conservative synthesis of published pediatric sleep guidance. Wake windows are a practical rule of thumb used by sleep specialists, not a clinical standard. Where each part of this page comes from:
- Wake window ranges: consistent with Cleveland Clinic, What Are Baby Wake Windows? And How Long Should They Be? Our upper bounds are kept on the careful side of that table.
- Total sleep context (16 to 17 hours a day for newborns): American Academy of Pediatrics, HealthyChildren.org: Getting Your Baby to Sleep
The naps-per-day column is the typical pattern families report at each age. It varies widely and is offered as context, not as a scientific claim.
Each link checked live on 2026-07-24. Claim: sleep.wake_windows_table.0_12m.v1, clinical review in progress.
Education, not medical advice
This calculator is for learning, not diagnosis. Every baby varies. If you are worried about your baby's sleep, breathing, feeding, or growth, talk to your pediatrician.
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