Week 40 of 52 · Month 10
Week 40: Your 40-Week-Old Baby
Stacks, bangs, and mouths toys to learn; stranger awareness is normal.
Wake window
3 hours to 4 hours
Total sleep
13–14 hrs / 24h
Naps
2–2 per day
Feeding
4–5 milk feeds + solids meals
Sleep at 40 weeks
At 40 weeks, most babies are awake for 3 hours to 4 hours at a stretch and sleep 13–14 hours across the full day, over 2–2 naps plus nighttime sleep. The first wake window of the day is usually the shortest and the last one before bed the longest — the wake-window calculator spreads them out for you.
Milestones to watch for
- Cruises along furniture
- Waves bye-bye
Development this week
Stacks, bangs, and mouths toys to learn; stranger awareness is normal.
What's normal this week
- Sleep: about 13–14 hours total, in 2 naps plus night sleep. Most sleep happens at night now; early-morning wakes are a common phase.
- Awake time: roughly 3 hours to 4 hours between sleeps. Stacks, bangs, and mouths toys to learn; stranger awareness is normal.
- Feeding: 4–5 milk feeds + solids meals a day is typical. Solids are practice and exploration — milk remains the main nutrition source this year.
Week 40 questions
How long should a 40-week-old be awake between naps?
Most 40-week-olds handle about 3 hours to 4 hours awake at a time. Watch for sleepy cues — staring off, jerky movements, fussing — and start the nap routine a few minutes before the top of the window.
How much sleep does a 40-week-old need in 24 hours?
Typical total sleep at 40 weeks is about 13–14 hours in 24 hours, usually split into 2 naps plus nighttime sleep. A day or two outside that range is common and usually not a concern on its own.
What milestones might I see at 40 weeks?
Around 40 weeks many babies begin to: cruises along furniture; waves bye-bye. Milestones are ranges, not deadlines — babies reach them across a span of weeks. Mention any concern to your pediatrician at the next visit.
Educational information only — not medical advice. Every baby develops and sleeps on their own timeline. If you have any concern about your baby's sleep, feeding, or development, talk to your pediatrician.