How Much Should a Newborn Sleep?

Newborns sleep a lot — typically 14–17 hours in every 24, according to WHO guidelines on sleep for children under five. The catch is that it doesn't come in one block, or even two. It comes in short, unpredictable bursts scattered across the day and night, with no regard whatsoever for your schedule, your hopes, or the fact that it is 3am.

This is completely normal. It is, for most new parents, also the first surprise.

What Newborn Sleep Actually Looks Like

A newborn sleep cycle is typically around 50 minutes, compared to an adult's 90-minute cycle (Patel et al., StatPearls, 2024). Within that cycle, newborns spend around half their total sleep in REM — significantly more than adults (Grigg-Damberger and Wolfe, J Clin Sleep Med, 2017). This is not a design flaw. REM sleep plays a crucial role in brain development in early infancy; less REM time in infancy has been associated with poorer developmental outcomes (Grigg-Damberger and Wolfe, J Clin Sleep Med, 2017).

The practical result is a baby who sleeps in stretches of 2–4 hours, wakes to feed, and goes back to sleep. Around the clock. This pattern is normal from birth until somewhere around 3 months, when sleep cycles begin to consolidate and longer stretches become more likely.

Some newborns sleep more than 17 hours. Some sleep closer to 14. Both are within the normal range, provided the baby is feeding well, gaining weight, and alert during wakeful periods. The number matters less than the overall picture.

Why Newborns Sleep So Much

Sleep in the newborn period is doing a great deal of work. According to Sundhedsstyrelsen (SST), brain growth in the first months of life is faster than at any other point — and a significant portion of that development happens during sleep (SST, Ernæring til spædbørn og småbørn). The high proportion of active sleep in newborns reflects this: sleep is when the brain processes, consolidates, and builds.

Newborns also have very small stomachs. They digest quickly, wake to feed, and then need to sleep again to process the energy. The cycle of sleep, feed, sleep isn't inefficiency — it's the system functioning as it should.

What disrupts it is overstimulation. A newborn's nervous system is immature and tires quickly. Too much input — noise, light, handling, activity — can make settling harder rather than easier. Some parents find their baby sleeps better with low background noise than in complete silence; others find the opposite. There is no universal rule. You will find yours.

Day and Night Confusion — and When It Sorts Itself Out

Newborns are not born knowing the difference between day and night. In the womb, melatonin from the mother regulated their sleep-wake rhythm. Outside it, they have to develop their own circadian rhythm — a process that begins gradually from around 5 weeks of age and takes several more weeks to consolidate (Wong et al., J Physiological Anthropology, 2022).

Until then, there is little point trying to enforce a day/night distinction through scheduling. What does help, gently, is keeping daytime feeds in lighter, livelier environments and night feeds quiet and dim. Not as training — the baby is too young for that — but as early signalling that these two parts of the day are different.

By 6–8 weeks, most babies begin shifting slightly more sleep to the night. By 3 months, longer overnight stretches become more common, though not guaranteed. The parents who sail through this phase and the ones who don't are mostly distinguished by their baby's temperament, not their technique.

When to Be Concerned About Sleep

Most variation in newborn sleep is normal. The things worth flagging to your midwife or health visitor are:

  • Persistent sleepiness and difficulty rousing — not responding to feeding cues, unusually lethargic (SST, Gulsot hos spædbørn)
  • Poor feeding alongside excessive sleep — fewer wet nappies than expected, slow weight gain (SST, Amning — en håndbog for sundhedspersonale)
  • Breathing irregularities during sleep — pauses lasting 20 seconds or more, laboured breathing, or unusual colour (Kondamudi et al., StatPearls, 2026)

Short pauses in breathing (periodic breathing) are common and normal in newborns. Sustained pauses, or breathing that looks like effort, are not.

If your baby is sleeping within the normal range, feeding well, and has good wet nappy output, there is very little to worry about — even if the distribution of that sleep feels completely unreasonable at 4am.

Frequently Asked Questions

Is it normal for a newborn to sleep all day? Yes, within limits. Newborns sleep 14–17 hours per 24 hours and have very short wakeful windows — sometimes as little as 45–60 minutes between sleeps. If your baby is difficult to wake for feeds or sleeping significantly more than 17 hours consistently, mention it to your midwife.

How long should a newborn sleep at night? There is no set amount. Newborns don't yet distinguish night from day, so overnight sleep looks much like daytime sleep — short stretches between feeds. Most newborns wake every 2–4 hours overnight in the early weeks. Longer stretches gradually emerge from around 6–8 weeks onwards.

Should I wake my newborn if they've slept too long? In the first weeks, yes — wake to feed if more than 3 hours have passed since the last feed. Once your baby has regained their birth weight and your health visitor is happy with growth, you can generally let them sleep. See our post on waking a sleeping newborn to feed for more detail.

When do newborns start sleeping longer at night? Most babies begin consolidating overnight sleep somewhere between 6 and 12 weeks. By 3 months, many (though not all) will have one longer stretch of 4–6 hours. This varies enormously between babies and is largely temperament-driven.

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