Your 4-month-old's sleep
At a glance: at this age your baby can stay awake for 1 h 30 min–2 h 30 min at a time, and needs 12–16 h of sleep per 24 hours.
Recommended awake time
1 h 30 min – 2 h 30 min
Number of naps
4
Total sleep per 24 h
12–16 h
Bedtime
8:00 PM
Sample schedule (4 months old)
Assuming a 7:00 wake-up — adjust it to your real wake-up.
- 7:00 AMWake up
- 8:48 AM – 9:48 AM Nap 1
- 11:36 AM – 12:36 PM Nap 2
- 2:24 PM – 3:24 PM Nap 3
- 5:12 PM – 6:12 PM Nap 4
- 8:00 PMBedtime 🌙
What’s happening with sleep now
Around four months, your baby's sleep goes through one of its biggest lifetime changes. Until now, newborn sleep was simple: deep or light, drifting easily from one to the next. Now the brain matures into more adult-like sleep cycles, moving through lighter and deeper stages and briefly surfacing between each one. This is real, permanent development, not a passing phase that later 'goes back' to how it was. People call it the four-month regression, but it's really a progression: your baby's sleep is growing up.
Because these cycles are shorter than a full stretch of sleep, your baby now wakes a little at the end of each one, usually every one to two hours. That's completely normal for a maturing brain. The reason it becomes so visible is that babies notice the change in surroundings when they surface. If they fell asleep being rocked or fed, they may look for that same feeling to link into the next cycle. Nothing is wrong, and nothing you did caused it.
The good news is that structure genuinely starts to help now. At this age babies do well on wake windows of about one and a half to two and a half hours, with roughly four naps a day and twelve to sixteen hours of sleep across twenty-four hours, around nine to ten hours at night and four to five in naps. A predictable rhythm and a calm, repeatable wind-down give your baby the cues they need to settle more easily through these new cycles.
Common challenges — and what helps
Suddenly waking every one to two hours all night, when they used to sleep in longer stretches.
This is the new sleep cycles surfacing, not a step backwards. Keep night responses calm, quiet and boring, with dim light and minimal talking. Where you can, let your baby practise settling at the start of the night by putting them down drowsy but awake, so they get used to the feeling of falling asleep in the cot. If they can find sleep there at bedtime, linking cycles overnight gets easier. Always follow safe sleep: baby on their back, on a firm flat surface, in their own clear space.
Naps have shrunk to a single short cycle of about thirty to forty-five minutes.
Short naps are extremely common right now because one sleep cycle ends and your baby fully wakes instead of joining the next. Watch age-appropriate wake windows of about one and a half to two and a half hours so they go down neither under- nor over-tired, and keep the nap environment dark and consistent. You can pause a moment before rushing in, since some babies resettle on their own. Short naps usually stretch out again as the cycles mature over the coming weeks.
Fighting bedtime and getting wired and overtired in the last stretch of the day.
Late afternoon and evening are when overtiredness builds, which makes settling harder, not easier. Protect the final wake window by keeping it on the shorter side and dimming lights and noise well before bed. Use the same short, calm wind-down every night, for example bath, feed, book, cot, so the sequence itself becomes a signal that sleep is coming. A baby who arrives at bedtime calm rather than frazzled settles far more smoothly.
What’s coming next
Over the next month or so, many babies begin easing from four naps toward three as each nap grows a little longer and more predictable. Nap consolidation tends to look like the morning and midday naps lengthening into more solid blocks, while a shorter third catnap holds the late afternoon together until bedtime. It rarely happens on a single day; you'll see good days and messy days as the rhythm settles. Following your baby's tiredness cues and keeping wake windows age-appropriate will carry you smoothly into the three-nap pattern.
What helps most right now
- Aim for wake windows of about one and a half to two and a half hours and let tiredness cues, not just the clock, tell you when it's time.
- Use the same brief, calm wind-down before every sleep so the routine itself signals that sleep is coming.
- When it goes well, practise putting your baby down drowsy but awake so they get used to falling asleep in their own cot.
- Keep safe sleep non-negotiable: back to sleep, firm flat mattress, no loose bedding, pillows or bumpers, and their own clear sleep space.
Safe sleep
Safe sleep (the essentials): your baby sleeps best and safest alone, on their back, in a clear cot — firm flat mattress, no pillows, duvets, bumpers or soft toys. Room-share without bed-sharing, especially before 6 months, and avoid overheating. If you ever have concerns about your baby’s breathing or rest, talk to your pediatrician.
When to check with your pediatrician
When to check with your pediatrician: sleep varies a lot from baby to baby, but do mention it to your doctor if you notice loud snoring, pauses in breathing, or very laboured breathing, if your baby isn’t gaining weight or is feeding poorly, if they consistently sleep far less (or more) than expected and seem unhappy or unusually drowsy, or if anything about their development worries you. This guide is general guidance and not a substitute for medical advice.
More free tools
General guidance for healthy babies — every child is different. This is not medical advice; talk to your pediatrician about your baby.
Want this calculated automatically, every day?
Nana learns your baby's real rhythm and adjusts nap times and bedtime as the day actually unfolds — not just by age. Free to start.