How Much Babies Sleep, By Age

Q: How many hours should a 6-month-old sleep?

The World Health Organization recommends 12 to 16 hours of good quality sleep including naps per 24 hours for babies aged 4 to 11 months. Real variation is much wider. In the Zurich Longitudinal Studies published in Pediatrics in 2003, mean total sleep at 6 months was 14.2 hours, with the 2nd percentile at 10.4 hours and the 98th at 18.1 hours. A number outside the band is not automatically a problem, and it is worth raising with the clinician who knows your baby. Sleeping unusually much is the exception that is not reassuring. The AAP says to call your child's doctor right away if a baby with a fever is unusually drowsy. The NHS puts the same territory higher: it says to call 999 or go to A&E if your baby is difficult to wake or cannot be woken. Act on the more urgent instruction.

Q: Is it normal for my baby to still wake at night at 12 months?

Yes. A 2018 study of 388 infants in Pediatrics found that, using thresholds of either 6 or 8 hours of uninterrupted sleep, between 27.9% and 57.0% of infants at 6 and 12 months did not sleep through the night. The authors report no significant associations between sleeping through the night and mental development, psychomotor development, or maternal mood, and write that expectations for early sleep consolidation could be moderated. HealthyChildren.org says frequent waking is developmentally appropriate and allows the baby to wake up when he is not getting enough oxygen or is having problems breathing. Waking is the expected finding. The opposite is the emergency: the NHS says to call 999 or go to A&E if your baby is difficult to wake or cannot be woken.

Q: How much do newborns sleep?

HealthyChildren.org, from the American Academy of Pediatrics, says that although newborns sleep about 16 to 17 hours per day, they may only sleep 1 or 2 hours at a time. The NHS says a newborn's total daily sleep varies but can be around 18 hours, and its Best Start in Life pages say some newborns sleep a total of around 8 hours a day while others sleep up to around 18, and either is perfectly normal. The NHS figure of 5 to 8 hours or longer at night belongs to its 3 to 6 month heading, not to newborns, so a newborn sleeping that long unbroken is worth raising with your midwife, health visitor or doctor. Sleepiness has a limit. The AAP says to call your child's doctor right away if a baby younger than 3 months (12 weeks) has a temperature of 100.4F (38.0C) or higher. The NHS goes higher still: it says to call 999 or go to A&E if your baby is difficult to wake or cannot be woken, or has a temperature of 38C or higher when under 3 months old.

Q: Are wake windows evidence-based?

Wake windows, meaning set awake intervals between sleeps at each age, do not appear in the World Health Organization, NHS, or HealthyChildren.org guidance on infant sleep. None of those bodies publishes an age-by-age awake interval. That does not prove the idea is useless, but the published sleep duration figures were not derived from wake windows, and none of these bodies treats a specific schedule as a standard your baby must meet. If your baby's sleep worries you, the NHS routing in the United Kingdom is to speak to your health visitor. If your baby is difficult to wake or cannot be woken, that is not a health visitor question. The NHS says to call 999 or go to A&E.

Q: What is the safe way for my baby to sleep?

What follows is part of the AAP's safe sleep list, not the whole of it. the cited list runs to roughly two dozen items and is published on the HealthyChildren.org page "How to Keep Your Sleeping Baby Safe: AAP Policy Explained". The AAP says babies up to 1 year of age should always be placed on their back to sleep during naps and at night, on a firm, flat sleep surface. A firm surface means it should not indent when your baby is lying on it, and the AAP's next sentence is "Any surface that inclines more than 10 degrees isn't safe for your baby to sleep on", which rules out propping a congested baby up on a wedge. Use a crib, bassinet, portable crib or play yard that meets Consumer Product Safety Commission standards, and keep soft objects and loose bedding out of it: pillows, quilts, comforters, mattress toppers, non-fitted sheets, blankets, toys and bumper pads. The AAP names three hazards, not one: entrapment, suffocation and strangulation. It says never to sleep with your baby, and to keep your baby's sleep space in your room but not in your bed for at least the first 6 months. If you swaddle, keep the baby on their back and stop swaddling when your baby looks like they are trying to roll over, typically around 3 to 4 months. Read the cited list for what is not covered here, including overheating, pacifiers, immunizations and tummy time.

Little Route Lab · Updated 2026-08-31 · 10 min read

The short answerBaby sleep varies widely by age and individual, so ranges are more useful than one required total. Track feeding, output, alert periods, and growth with your clinician rather than forcing a schedule. For every sleep, place the baby on their back in a clear, firm, flat, non-inclined sleep space. Call emergency services if a baby cannot be woken, struggles to breathe, has a seizure, or shows blue, grey, pale, or blotchy colour; on brown or black skin, check palms and soles.

The short answer

There is no single correct number of hours. The bodies that publish figures publish wide bands rather than targets, and healthy babies land outside those bands in both directions.

One exception runs opposite to most parental worry: a baby sleeping unusually much is not automatically fine. The NHS lists a baby who is difficult to wake, or cannot be woken, under immediate action required, and the AAP lists a baby with a fever who is unusually drowsy as a reason to call the doctor right away. Read the next section first.

When to get help now

Call 999 or go to A&E, which is the NHS instruction, or call your own country's emergency number, if your baby has any of the following. All 11 bullets the NHS publishes under "Immediate action required" for babies and children under 5 are here, each one whole, reviewed 6 August 2026. Nothing has been moved to a calmer tier.

Swollen lips, tongue or throat with difficulty swallowing or talking.
Breathing very fast, or difficulty breathing. The NHS notes they may make grunting noises or suck in their tummy when they breathe.
"Has blue, grey, pale or blotchy (mottled) skin, lips or tongue – on black or brown skin, this may be easier to see on the palms of their hands or soles of their feet". That is the NHS bullet on the cited page. Its second half tells you where to look on black or brown skin: the palms and the soles.
Skin that feels cold or damp (clammy) to touch.
A rash that does not fade when you press it.
A very high temperature, meaning 38C or higher in babies under 3 months old, or 39C or higher in babies 3 to 6 months old.
A very low temperature, meaning less than 36C, or feels cold to touch or is shivery.
A weak, high-pitched or continuous cry.
Has fainted, is difficult to wake, or cannot be woken.
Has not had a pee in the past 12 hours.
Is having a seizure (fit).

The same NHS page carries a second, less urgent tier. Call NHS 111 if you are worried about any of your child's symptoms or do not know what to do. That is a UK service. Outside the UK, use your own urgent advice line.

The American Academy of Pediatrics publishes a separate fever list. It says to call your child's doctor right away if your child has a fever and any of the following. These are all 8 items on that page's "call your child's doctor right away" tier, the most urgent tier that page has. A second, calmer list follows.

Looks very ill, is unusually drowsy, or is very fussy.
Has been in a very hot place, such as an overheated car.
Has other symptoms, such as a stiff neck, severe headache, severe sore throat, severe ear pain, breathing difficulty, an unexplained rash, or repeated vomiting or diarrhea.
Has immune system problems, such as sickle cell disease or cancer, or is taking steroids or other medicines that could affect their immune system.
Has heart problems that may affect how she tolerates a fever and increased heart rate as a result of the fever.
Has had a seizure.
Is younger than 3 months (12 weeks) and has a temperature of 100.4F (38.0C) or higher.
Temperature rises above 104F (40C) repeatedly, for a child of any age.

The same AAP page also says to call your child's doctor if your child still "acts sick" once their fever is brought down, seems to be getting worse, or has a fever lasting more than 24 hours under age 2 or more than 72 hours at 2 and older. That is the slower AAP tier. It does not replace the NHS list above: if any sign on that list is present, call 999 or go to A&E now.

If you are worried about your baby right now, you do not need a reason that satisfies anyone. Call your pediatrician, your local out-of-hours service, or your emergency number. Trusting your instinct is the correct response.

What the age bands actually say, and who says them

World Health Organization, 2019. For babies under 1 year, good quality sleep including naps: 14 to 17 hours at 0 to 3 months of age, and 12 to 16 hours at 4 to 11 months of age.

American Academy of Pediatrics, via HealthyChildren.org. Although newborns sleep about 16 to 17 hours per day, they may only sleep 1 or 2 hours at a time.

NHS (United Kingdom). The NHS files each figure under an age heading, kept here because one is often quoted against the wrong age. Under newborns: most newborn babies are asleep more than they are awake, and their total daily sleep varies but can be around 18 hours. Under sleep requirements at 3 to 6 months old: as your baby grows, they will need fewer night feeds and may be able to sleep for longer, and some babies may sleep for 5 to 8 hours or longer at night, but not all. That 5 to 8 hour stretch is a 3 to 6 month figure, not a newborn one, and a newborn sleeping that long unbroken is worth raising with your midwife, health visitor or doctor. Under 6 to 12 months: some babies will sleep for around 15 hours, most of this at night. From 12 months: babies will sleep for around 12 to 15 hours in total after their first birthday.

The NHS Best Start in Life pages put the newborn range more starkly: some newborns may sleep around 8 hours a day, others up to around 18, and the page says either is perfectly normal. It also relays a figure that is not the NHS's own. A survey by The Lullaby Trust, a charity rather than a health body, found 59% of parents of babies under 12 months say their baby sleeps less than 4 hours at a time.

For ordinary sleep worries the NHS routing is UK-specific: speak to your health visitor. Outside the UK, that goes to whoever provides your baby's routine care.

Why the ranges are so wide

The clearest picture of normal variation is the Zurich Longitudinal Studies, published in Pediatrics in February 2003, which followed 493 subjects. At 6 months, Table 1 gives mean total sleep across 24 hours of 14.2 hours, a 2nd percentile of 10.4 hours and a 98th percentile of 18.1 hours. Two babies at those percentiles are both inside the reference range.

The authors add their own caveat. Because sleep onset and wake-up time may be difficult to define by subjective assessment, the durations reported there should in general be interpreted as time spent in bed. That is variation, not a target.

Night waking is normal, and the research says so directly

A 2018 study in Pediatrics assessed 388 infants at 6 and 12 months. Using thresholds of either 6 or 8 hours of uninterrupted sleep, between 27.9% and 57.0% of infants did not sleep through the night. The authors report no significant associations between sleeping through the night and mental development, psychomotor development, or maternal mood. They did find that sleeping through the night was associated with a much lower rate of breastfeeding (P < .0001). Their conclusion is hedged and quoted at that strength: expectations for early sleep consolidation could be moderated. That is a suggestion, not an instruction.

HealthyChildren.org goes further. It says frequent waking is developmentally appropriate and allows the baby to wake up when he is not getting enough oxygen or is having problems breathing. The same page says sleeping undisturbed for prolonged periods at this age is not healthy.

How sleep changes over the first year

The Zurich authors report a small increase of nighttime sleep duration by age 1 year, from a mean of 10.0 hours at 3 months to 11.7 hours at 1 year, alongside a decreasing trend in daytime sleep. Sleep did not so much increase over the first year as migrate into the night. In the same study all infants napped in the first 12 months. Table 1 gives mean daytime sleep of 3.4 hours at 6 months, 2.8 hours at 9 months and 2.4 hours at 12 months. At 18 months of age there was a significant change from 2 or more naps to only 1 nap per day, later than many parents expect.

One newborn breathing pattern frightens parents. The AAP describes breathing that is often irregular and may stop for 5 to 10 seconds, a condition it calls normal periodic breathing of infancy, then starts again with a burst of rapid breathing at 50 to 60 breaths a minute. Babies generally outgrow it by about the middle of the first year. The discriminator is the part that matters: the AAP says the baby's skin colour does not change with those pauses, in contrast with apnea. Any colour change in the skin, lips or tongue, laboured breathing, or very fast breathing belongs on the emergency list above.

Wake windows, and the honest limits of the evidence

Wake windows, meaning prescribed lengths of awake time between sleeps at each age, do not appear in the World Health Organization, NHS, or HealthyChildren.org guidance this article cites. None of those bodies sets an age-by-age awake interval, and none of the hour figures here were derived from one. That is a statement about what they have published, not proof the concept is useless.

Safe sleep, and where to read the rest of the list

The AAP's safe sleep guidance runs to roughly two dozen recommendations. What follows is part of that list, not the whole of it. Read the whole list on the AAP page linked in Sources, "How to Keep Your Sleeping Baby Safe: AAP Policy Explained".

Put your baby on their back for all naps and at night, up to 1 year of age.
Use a firm, flat sleep surface. A firm surface means that it shouldn't indent when your baby is lying on it. The AAP's next sentence supplies the test: "Any surface that inclines more than 10 degrees isn't safe for your baby to sleep on." That rules out propping a congested baby up on a wedge to sleep.
Place your baby in a crib, bassinet, portable crib or play yard that meets the safety standards of the Consumer Product Safety Commission.
Keep soft objects and loose bedding out of your baby's sleep area. The AAP names pillows, quilts, comforters, mattress toppers, non-fitted sheets, blankets, toys and bumper pads, and its SIDS prevention page adds sheepskins and stuffed toys. It names three hazards, not one: entrapment, suffocation and strangulation.
The AAP says never to sleep with your baby. If you bring your baby into your bed to feed or comfort them, place them in their own sleep space when you are ready to sleep. Keep that space in your room, not in your bed, for at least the first 6 months.
Swaddle if you like, but the AAP says swaddling does not reduce SIDS risk. Keep the baby on their back when swaddled, and stop swaddling when your baby looks like they are trying to roll over, typically around 3 to 4 months.
Do not let your baby get overheated. The AAP says your baby only needs one more layer than you would wear in the same environment, and not to put a hat on indoors once you are home from the hospital.
Do not rely on a home cardiorespiratory monitor: the AAP says there is no evidence these devices decrease SIDS risk.

Items not reproduced here include prenatal care, smoking and nicotine, alcohol and drug use, breastfeeding, pacifiers at sleep times, immunizations, weighted sleepwear, car seats and swings, and daily tummy time.

What this page is and is not

This article explains general guidance published by named health bodies, naming which body said what and in which country. It is not advice about your baby. Anything specific to your baby belongs with the clinician who knows their history, and if any sign in the emergency list above is present, act on it now.

Continue with safe sleep for babies and milestone ranges first year.

Sources

WHO guidelines on physical activity, sedentary behaviour and sleep for children under 5, World Health Organization, 24 April 2019.
Getting Your Baby to Sleep, AAP.
Sleeping Through the Night, AAP.
Stages of Newborn Sleep, AAP.
Helping your baby to sleep, NHS.
Your baby's sleep patterns, NHS Best Start in Life.
When to get urgent medical help for babies and children under 5, NHS, reviewed 6 August 2026.
Fever: When to Call the Pediatrician, AAP.
Safe Sleep: Ways to Reduce a Baby's Risk of SIDS and Suffocation, AAP.
How to Keep Your Sleeping Baby Safe: AAP Policy Explained, AAP.
Iglowstein I, Jenni OG, Molinari L, Largo RH. Sleep Duration From Infancy to Adolescence. Pediatrics 111(2), 2003, 302-307.
Pennestri MH and colleagues. Uninterrupted Infant Sleep, Development, and Maternal Mood. Pediatrics 142(6), 2018, e20174330.

Parents also ask

How many hours should a 6-month-old sleep?

The World Health Organization recommends 12 to 16 hours of good quality sleep including naps per 24 hours for babies aged 4 to 11 months. Real variation is much wider. In the Zurich Longitudinal Studies published in Pediatrics in 2003, mean total sleep at 6 months was 14.2 hours, with the 2nd percentile at 10.4 hours and the 98th at 18.1 hours. A number outside the band is not automatically a problem, and it is worth raising with the clinician who knows your baby. Sleeping unusually much is the exception that is not reassuring. The AAP says to call your child's doctor right away if a baby with a fever is unusually drowsy. The NHS puts the same territory higher: it says to call 999 or go to A&E if your baby is difficult to wake or cannot be woken. Act on the more urgent instruction.

Is it normal for my baby to still wake at night at 12 months?

Yes. A 2018 study of 388 infants in Pediatrics found that, using thresholds of either 6 or 8 hours of uninterrupted sleep, between 27.9% and 57.0% of infants at 6 and 12 months did not sleep through the night. The authors report no significant associations between sleeping through the night and mental development, psychomotor development, or maternal mood, and write that expectations for early sleep consolidation could be moderated. HealthyChildren.org says frequent waking is developmentally appropriate and allows the baby to wake up when he is not getting enough oxygen or is having problems breathing. Waking is the expected finding. The opposite is the emergency: the NHS says to call 999 or go to A&E if your baby is difficult to wake or cannot be woken.

How much do newborns sleep?

HealthyChildren.org, from the American Academy of Pediatrics, says that although newborns sleep about 16 to 17 hours per day, they may only sleep 1 or 2 hours at a time. The NHS says a newborn's total daily sleep varies but can be around 18 hours, and its Best Start in Life pages say some newborns sleep a total of around 8 hours a day while others sleep up to around 18, and either is perfectly normal. The NHS figure of 5 to 8 hours or longer at night belongs to its 3 to 6 month heading, not to newborns, so a newborn sleeping that long unbroken is worth raising with your midwife, health visitor or doctor. Sleepiness has a limit. The AAP says to call your child's doctor right away if a baby younger than 3 months (12 weeks) has a temperature of 100.4F (38.0C) or higher. The NHS goes higher still: it says to call 999 or go to A&E if your baby is difficult to wake or cannot be woken, or has a temperature of 38C or higher when under 3 months old.

Are wake windows evidence-based?

Wake windows, meaning set awake intervals between sleeps at each age, do not appear in the World Health Organization, NHS, or HealthyChildren.org guidance on infant sleep. None of those bodies publishes an age-by-age awake interval. That does not prove the idea is useless, but the published sleep duration figures were not derived from wake windows, and none of these bodies treats a specific schedule as a standard your baby must meet. If your baby's sleep worries you, the NHS routing in the United Kingdom is to speak to your health visitor. If your baby is difficult to wake or cannot be woken, that is not a health visitor question. The NHS says to call 999 or go to A&E.

What is the safe way for my baby to sleep?

What follows is part of the AAP's safe sleep list, not the whole of it. the cited list runs to roughly two dozen items and is published on the HealthyChildren.org page "How to Keep Your Sleeping Baby Safe: AAP Policy Explained". The AAP says babies up to 1 year of age should always be placed on their back to sleep during naps and at night, on a firm, flat sleep surface. A firm surface means it should not indent when your baby is lying on it, and the AAP's next sentence is "Any surface that inclines more than 10 degrees isn't safe for your baby to sleep on", which rules out propping a congested baby up on a wedge. Use a crib, bassinet, portable crib or play yard that meets Consumer Product Safety Commission standards, and keep soft objects and loose bedding out of it: pillows, quilts, comforters, mattress toppers, non-fitted sheets, blankets, toys and bumper pads. The AAP names three hazards, not one: entrapment, suffocation and strangulation. It says never to sleep with your baby, and to keep your baby's sleep space in your room but not in your bed for at least the first 6 months. If you swaddle, keep the baby on their back and stop swaddling when your baby looks like they are trying to roll over, typically around 3 to 4 months. Read the cited list for what is not covered here, including overheating, pacifiers, immunizations and tummy time.

Independent guidance, not medical advice. We do not diagnose or recommend treatments or doses. For any concern about your baby, contact your pediatrician or local emergency service.