Wake Window Calculator
Find out exactly how long your baby should be awake — based on their age, right now.
Why Wake Windows?
Wake windows are one of the most powerful tools for better baby sleep, and one of the most commonly misunderstood.
Too long awake and your baby becomes overtired, fights sleep, and wakes more frequently overnight. Too short and they won't have built enough sleep pressure to nap well. Get it right and everything starts to fall into place! Naps lengthen, nights improve, and bedtime gets easier.
The problem is that wake windows change constantly in the first year. What worked at 8 weeks won't work at 4 months. What works at 6 months shifts again by 9 months. It's a moving target, and most parents don't realize their baby's schedule needs adjusting until things have already gone wrong.
This calculator takes your baby's date of birth and tells you their recommended wake windows right now — along with a sample schedule for today, and a heads-up on what sleep changes are coming next.
How It Works
1. Enter your baby's birthday We calculate their exact age in weeks and months to give you the most accurate wake windows for right now.
2. Get your personalised results You'll see recommended wake windows, number of naps, total day sleep targets, and a sample schedule for both a solid nap day and a short nap day.
3. Get milestone updates by email As your baby hits each new sleep stage, we'll send you a free update with new wake windows and guidance — so you're always one step ahead.
Wake window calculator
Enter your details and your baby's birthday. We will show you their recommended wake windows, a sample schedule, and what is coming next — plus send you free milestone updates as they grow.
Day / Month / Year
recommended wake window
Sample schedules (based on 7am wake)
Solid nap day
Short nap day
What's coming up
These are average guidelines. Most babies fall within 15 to 30 minutes of suggested wake times. Always follow your baby's cues. This is not medical advice — consult your health visitor or GP with any concerns.
Understanding Your Results
Wake window: the amount of time your baby should be awake between sleeps, from the moment they wake up to the moment they're fully asleep again.
Solid nap day: a sample schedule based on your baby getting full, age-appropriate naps. Use this as your target.
Short nap day: a sample schedule for the days when naps are short or interrupted. Bedtime shifts earlier to compensate and prevent overtiredness.
What's coming up: a heads-up on the next sleep milestone or transition so you can prepare rather than be caught off guard.
FAQs
My baby seems tired before the wake window is up, what should I do?
1
Always follow your baby's cues first. If they're showing clear tired signs like rubbing eyes, glazed look, losing interest in play, put them down even if the full wake window isn't up. The calculator gives you a target, not a rule.
My baby won't sleep even after a full wake window, what's wrong?
2
A few things can cause this: undertiredness (wake window too short), overtiredness (wake window too long), or sleep associations. If it's consistent, try adjusting the wake window by 10–15 minutes in either direction over a few days and see what changes.
The calculator shows a different number of naps than my baby is on, is that okay?
3
Yes, nap transitions happen gradually and every baby moves at their own pace. If your baby is happily on fewer naps than the calculator suggests and sleeping well, trust what's working. The calculator shows typical averages, not rigid rules.
My baby is premature — should I adjust the age I enter?
4
Yes , use your baby's corrected age (based on their due date, not their birth date) until they reach around 12 months corrected. This gives you more accurate wake window guidance for where they actually are developmentally.