Wake windows vs. 'by the clock' schedules: Which is right for my child?

Are you looking to set up the ideal sleep schedule for your little one but unsure where to start? Figuring out when your kiddo should sleep can feel overwhelming, especially coupled with all of the other things on parents’ plates. Then it can feel like something changes every time sleep is going well! 

While there’s usually not a magic wand to wave when it comes to kiddos and sleep, there are a couple of methods that can help you craft an age-appropriate schedule that fits your child’s needs. There are typically two ways to go about it: using wake windows (how long a child can comfortably stay awake) or the clock to determine sleep times. 

In this article, we’ll walk you through the pros and cons of both types of sleep schedules, give tips for setting up a sleep schedule, and answer frequently asked questions about helping your little one get the sleep they need. 

IN THIS ARTICLE: 

Understanding wake windows 

What is a wake window? 

A “wake window” is how long a child can comfortably stay awake between sleep periods. It’s expected that newborns will have very short wake windows (30 - 90 minutes) and they will increase as your baby grows over their first year and beyond. For example, 6 month old wake windows are typically 2 - 3 hours. By the time a child is 2 years old, their wake windows are usually around 5.5 - 6 hours!  

Wake windows are helpful because they help determine how many naps your little one will take each day. Shorter wake windows translate to more naps. For example, it’s normal for 4 month olds to take 3 - 4  naps per day and 10 month olds to take 2 naps per day, since they can comfortably stay awake longer. 

Keep in mind that wake windows can vary by age, as well as the individual child, time of day, and even from one day to the next. For example, a 4 month old’s wake windows are typically 1.5 - 2.5 hours, so it’s not uncommon for them to comfortably stay awake 90 or so minutes during one awake period and over two hours the next. They may be tired and ready for sleep in under 2 hours at another point that same day. The next day may look entirely different too and that’s normal. 

Many children do well following wake windows that correspond to the times below, but that’s not always the case either. Treat these numbers as guidelines and know it’s OK if your kiddo’s wake windows don’t fit in these ranges — some children do best with more or less sleep. When determining if your child is getting enough shuteye, we also recommend evaluating their overall mood and energy levels.

Wake windows and sleepy cues 

For babies younger than 6 months, we recommend paying attention to a child’s sleepy cues (signs that your baby is getting tired) and wake windows when determining when to offer a nap. Common baby sleepy cues include: 

• Yawning 

• Reduced responsiveness 

• Droopy eyelids 

• Red eyebrows

• Glazed expression 

• Slowing in activity levels/interest 

• Drowsiness 

Note other behaviors like fussiness, crying, eye rubbing, and irritability are late sleepy cues and can indicate overtiredness. Aim to offer a nap to your little one before they exhibit these behaviors to ensure quality sleep. 

Benefits of wake windows 

A schedule based on wake windows is often most successful for babies under 6 months because sleep is primarily dictated by sleep pressure (tiredness) and hunger at this age instead of their internal clock []. Younger babies aren’t quite ready for a rigid clock-based sleep routine until their sleep-wake cycles are more mature, usually after 6 months or once your little one has transitioned to two naps. You can try a clock-based schedule after 6 months, but it will likely be more effective following the transition to two naps (typically by 8 - 9 months of age).

The primary benefit of a wake window schedule is that it works with your baby’s natural sleep needs, helping to avoid overtiredness — which can make it harder for them to fall asleep and stay asleep. By paying attention to how long your little one can stay awake between naps (instead of sticking to strict clock times), you can follow their sleep cues and make falling asleep easier. This approach is flexible and grows with your baby, making naps smoother and improving overall sleep for younger babies.

Challenges of using wake windows

Like anything, a schedule based on wake windows has some drawbacks too. One is that it can be difficult to keep track of wake windows throughout the day. Remembering what time your child woke up can be daunting, especially in those first few months when they take many naps and you’re likely exhausted too! (However, we can help there — the free app offers quick and easy sleep tracking. And with a Plus or Premium membership, you’ll gain access to our that helps take the guesswork out of wake windows.) 

As babies grow, a schedule based solely on wake windows may no longer be ideal because their internal body clock (aka circadian rhythm) becomes more established. After 6 months, sleep is influenced by tiredness (sleep pressure) and the time of day. Older babies usually do better with a more consistent, clock-based routine that helps regulate their naps and bedtime. Once your baby transitions to a 2-nap schedule, a clock-based routine that still accounts for wake windows but remains consistent each day can be more effective.

Benefits and challenges of a schedule based on wake windows 

Exploring 'by the clock' schedules

What is a 'by the clock' schedule?

A “by the clock” schedule is just that — you set your child’s sleep schedule using set times of day instead of solely focusing on wake windows. This typically works best for babies over 6 months (when their sleep-wake pattern becomes regulated by their internal clock []) or once they’re taking 2 naps per day, usually around 8 - 9 months. 

Note that even when you’re using a “by the clock” schedule you’ll want to consider your child’s age-appropriate wake windows to set nap times and bedtime. As your child gets older, you’ll need to adjust the schedule by gradually lengthening wake windows. However, if your little one wakes up early or takes a shorter or longer nap than usual on a given day, you’ll generally stick to the same schedule regardless.    

Benefits of a 'by the clock' schedule

A “by the clock” schedule establishes a consistent daily routine, which helps regulate a child’s circadian rhythm (or body clock). This can promote better sleep patterns and quality []. A clock-based schedule can also lead to more predictability for parents — it’s often easier to make plans and coordinate activities when you know when your child will nap and go to bed. 

You’ll also be able to skip the mental math of keeping track of when your little one wakes up and when they’ll need to take their next nap. This can be a relief for many parents. However, keep in mind that babies under 6 months are usually not ready for this type of schedule because sleep pressure (tiredness) still dictates their sleep times in those first few months. In fact, we typically recommend waiting until a baby has transitioned to a 2-nap schedule (by 8 - 9 months) before introducing a clock-based schedule. That said, twins may benefit from a clock-based schedule a bit earlier, closer to 6 months, to help manage both babies' needs more consistently.

A clock-based schedule can also help address issues like early rising. By keeping a consistent nap and bedtime, you can guide your child’s internal clock to follow a more predictable sleep-wake cycle. Over time, this consistency can help reduce early morning wake-ups, as your child's internal clock becomes more regulated. When children rise too early, it often signals that their sleep schedule is out of sync with their natural circadian rhythm, and a clock-based approach can help correct that by encouraging them to stay asleep until the desired time.

Drawbacks of a 'by the clock' schedule

A common challenge of a “by the clock” schedule is that it may not align with your little one’s natural sleep cues. For example, if your child’s set morning nap time is 10 AM but they’re already tired at 9 AM, staying awake for that extra hour may lead to overtiredness. Overtiredness can then make it harder for little ones to fall asleep and stay asleep. 

Having a mismatched schedule may happen more frequently if your kiddo is in the midst of a , sick, or extra tired while working on a developmental milestone. In certain situations, you may consider temporarily adjusting your little one’s schedule to account for any external factors that impact sleep. Consistent schedules are great, but feel free to adapt as necessary! 

The predictability of “by the clock” sleep times often makes it easier to set plans, however this type of schedule can also feel more rigid. Parents may feel “nap trapped” when their child needs to be home to sleep at specific times of day. This may be especially true if your child isn’t used to sleeping in different environments and/or you’re juggling with different schedules. 

It can also be tricky to determine an age-appropriate schedule for your child as they grow, especially if you’re dealing with issues like early rising or short naps. With , you can receive personalized analysis from a sleep consultant who reviews your child’s specific patterns to help tailor a schedule that best suits their needs.

Benefits and challenges of a 'by the clock' schedule 

Wake windows and 'by the clock' schedules: When to use a combined approach

For children over 6 months, there may be instances when using both approaches are useful. Using wake windows and “by the clock” can work well when little ones are in the midst of a nap transition and can benefit from some flexibility in their schedule. 

For example, if your baby is dropping from at around 8 - 9 months, you may set a morning nap time by the clock but adjust based on their wake window if they wake up early that morning or are especially tired as they get used to this new schedule. We recognize that this may not always be possible for some families due to scheduling constraints. Feel free to modify your child’s schedule as necessary to avoid overtiredness and promote quality sleep. It’s normal for kiddos to take some time to adjust to a new schedule — this is often the case for adults too! 

Both approaches can be especially useful in situations like traveling, where routines are disrupted. In these cases, using the clock for structure but allowing flexibility with wake windows can help prevent overtiredness and support better sleep. It's important to stay flexible and modify your child’s schedule as necessary to meet their needs.

A combination approach can also be helpful when your child is with a different caregiver during the week, and their schedule is outside of your control. For instance, you might use a wake window-based schedule during the week to provide flexibility, while relying on a clock-based schedule during the weekends to maintain consistency. This allows for some structure while still adapting to varying routines and preventing overtiredness.

Age considerations for sleep schedules overview

Newborns (0 - 3 months)

Newborns are still getting used to life outside the womb and need a lot of sleep each day (around 16 - 17 hours []). It’s normal for at this stage and young babies won’t follow a predictable schedule. Instead, sleep times will largely be determined by sleep pressure (tiredness) and hunger since their circadian rhythms aren’t developed yet. Wake windows (typically 30 - 90 minutes) and sleepy cues are generally the best predictors of when it’s time for newborns to sleep again.     

Infants (3 - 12 months) 

3 - 6 months 

Wake windows will increase as babies grow and develop. At 3 months, infant wake windows are typically 1 - 2 hours and by 6 months, wake windows are generally 2 - 3 hours. 

For this age group, we continue to recommend following a schedule based on age-appropriate wake windows and sleepy cues. 

6 - 12 months

Your little one’s wake windows will continue to increase in the second half of their first year. At 6 months, wake windows are typically 2 - 3 hours and they’re generally 3.25 - 4 hours by their first birthday. 

Around 6 months, a baby’s sleep-wake cycle will start to be governed by their internal clock (aka circadian rhythm []) instead of primarily by sleep pressure. Parents who wish to use a “by the clock” schedule may be able to do so at around 6 months, though some babies have more success with this once they’re taking two naps per day at around . 

Toddlers (1 - 3 years) 

At 1 year, toddlers can usually comfortably stay awake 3.25 - 4 hours. At 2 years old, wake windows are typically 5.5 - 6 hours. At 3 years, wake windows can be 6 - 6.5 hours (if your child is still napping). 

Toddlers typically transition from per day between 14 - 18 months. If they haven’t been on a “by the clock” schedule while taking two naps each day, a 1-nap schedule often lends itself well to this structure. Aim for one midday nap around the same time every day. 

Preschoolers (3 - 5 years) 

Children may continue napping at 3, while others have transitioned away from . If this is the case, we recommend implementing “rest time” instead of a daily nap. Setting an early bedtime is often beneficial for preschoolers who have stopped napping so they continue to get adequate overnight sleep (around 11.5 hours).

For 4 - 5 year olds, a is recommended, but it may shift a little later as your preschooler is able to stay awake longer without a nap.   

Tips for implementing a sleep schedule

Tip #1: Consider your child’s age and wake windows 

Following sleepy cues and wake windows can be helpful when timing newborn sleep, but we won’t expect young babies to be on a set schedule. Newborn sleep is chaotic and unpredictable! 

After 3 months, creating an age-appropriate sleep schedule can help set your child up for success when it comes to getting the rest they need to grow and develop. For children under 6 months (and potentially older), we recommend a daily “schedule” based on typical wake windows and sleepy cues. At this age, sleep times and durations will likely change from nap to nap — that’s expected and normal! Every day will likely look a little (or a lot!) different. 

Naps based on set times of day are typically best for children over 6 months (or babies who’ve dropped to two naps). In this case, aim to create a “by the clock” schedule that considers how long your child can comfortably stay awake. As with younger babies, these clock schedules will evolve as children can stay awake longer and go through various nap transitions.

Tip #2: Establish a daytime sleep routine 

A helps little ones know what to expect and that sleep is coming — for naps too! We recommend a shortened version of your little one’s bedtime routine before daytime sleep. Aim to do the same set of activities (like diaper change and snuggles) before each sleep session. 

Tip #3: Set a consistent morning rise time

We know that waking your little one up in the morning sounds counterintuitive — solo time to start your day can be a treat! However, when a child wakes up at the same time every day, and is exposed to bright light (open those curtains and turn on the lights!) it can help regulate the rest of the day. This can be particularly beneficial for babies around 2 - 3 months old. 

Tip #4: Learn your child’s sleepy cues

If you notice that your child displays when they’re getting tired, try using them to your advantage to help you time sleep sessions. Sleepy cues can help determine sleep times, but they can be a little tricky too. It may take time to learn your child’s sleepy cues — that’s OK! Additionally, some children may exhibit many sleep cues while others display few or zero. They may also be fleeting and easy to miss. Note that sleepy cues become less reliable as babies grow into toddlers and they may start masking their tiredness.

Tip #5: Limit individual naps to 2 hours

Regardless of the schedule you’re following, we suggest capping individual naps to no more than 2 hours each to avoid inadvertently taking away sleep from subsequent naps and/or night sleep. However, you know your kiddo best — if they’re sick or there’s another factor at play where they need the extra shuteye, that’s OK too. 

Tip #6: Be prepared to adapt as your little one grows and develops 

Just when you get into a good sleep groove with your little one — boom! — it changes. We understand this can be quite frustrating, but it’s normal. Children’s sleep needs evolve as they grow and multiple nap transitions are expected over their first few years. 

Aim to use the tips above to adjust and adapt your kiddo’s schedule as necessary. There are bound to be some in the road, whether due to your child needing a schedule change, developmental milestones, sickness, travel, welcoming a new sibling, etc. 

Tip #7: Set a consistent bedtime

Once you're following a clock based schedule, the best approach is to keep bedtime within the same 30-minute window each night by adjusting nap times. This helps regulate sleep-wake cycles. If a late nap is pushing bedtime too far back, it's fine to wake your child to maintain a consistent bedtime. If your child seems to regularly be awake too long before bed, you can extend wake times between naps to shift the last nap later. Adjusting your child’s bedtime based solely on when the last nap ended can lead to a kiddo who's overtired and struggles to fall asleep some nights or stays up too late on others.

Tip #8 Watch for overtiredness 

Like most things, sleep schedules aren’t going to be perfect. Life happens! There are bound to be short naps and skipped naps (and mistimed naps). While this is common and expected, do your best to help your child avoid . 

Sleep generally won’t go  off the rails from one missed nap. However, if a kiddo is perpetually too tired, or their bedtime varies quite a lot, it can make it harder for them to fall asleep and stay asleep, perpetuating a cycle of poor sleep. Although ideally we want to aim for a consistent bedtime after 6 months of age, we can move bedtime earlier by up to 60 minutes on occasion.

Takeaway

• Wake windows refer to time babies and children can comfortably stay awake before needing to sleep again. These periods are very short for young babies (30 - 90 minutes for newborns) and lengthen as children grow and develop (3.25 - 4 hours for 12 month olds). We typically recommend determining sleep times based on wake windows and sleepy cues for children under 6 months. 

• A “by the clock” schedule consists of specific sleep times for your child, based on age-appropriate wake windows and the number of naps they’re taking. These set sleep times typically won’t change, even if your little one wakes up early or takes a short (or longer than usual) nap. This type of schedule is usually most successful for babies over 6 months or when they’ve dropped to 2 naps per day.

• Tips for setting a sleep schedule include considering your child’s age and typical wake windows, setting a consistent nap routine, learning your baby’s sleep cues, adapting as your kiddo grows and requires schedule adjustments, and watching for overtiredness.