Overtired Vs. Undertired?
If you're waking up multiple times a night wondering why your baby can’t seem to stay asleep, you're not alone. One question I hear a lot is “how do I know if my baby is overtired or undertired?” when they are facing bedtime struggles!
It’s a frustrating puzzle — and while daily schedules and wake windows play a big role, we have to remember that they are not the only factor at play. Let's take a look at the bigger picture of night waking and how to tell if your baby's schedule might be the culprit before we get into how to tell the difference between overtired and undertired!
Common Causes of Night Wakings
Before we jump into the overtired vs. undertired discussion, it's important to mention that sleep disruptions can also be caused by:
👋🏼 Hunger – especially for younger babies or during growth spurts
👋🏼 Developmental Leaps– think learning to talk, walk, roll, crawl
👋🏼 Sleep associations – like needing to be fed, rocked, or held to fall asleep
👋🏼 Sleep environment – light, sound, temperature, or movement disruptions
These are all important to rule out, but once those boxes are checked, I often look at timing — because the timing of night wakes can give big clues.
Overtired vs. Undertired
When I work with families one-on-one, I’m constantly looking for patterns in how their baby is waking up at night. Based on that, I can usually tell if the daytime schedule needs a few adjustments.
Let’s break it down:
Signs Your Baby Might Be Overtired
An overtired baby has passed the point of “ripe and ready to sleep” and has entered that wired, restless, cortisol-fueled state that makes falling and staying asleep much harder. We even have a phrase in the sleep consulting world that says “an overtired baby has a harder time falling asleep and staying asleep!” so we want to really try to prevent over tiredness if possible!
Here are some classic signs:
+Falls asleep quickly at bedtime but then wakes up 20–45 minutes later
+ Multiple wakes in the first 2–3 hours of the night
+ Sleeps okay for a stretch (around 10pm–1am), then wakes again
+ Frequent wakings from 3am onward, often crying or agitated
Signs Your Baby Might Be Undertired
An undertired baby hasn’t had quite enough awake time during the day, which can make settling at bedtime tough — and cause sleep disruptions later in the night.
Here’s what that might look like:
+Takes 20+ minutes to fall asleep at bedtime and resists sleep
+ Sleeps well during the first half of the night (3–4 hours uninterrupted)
+ Wakes more in the second half of the night (midnight to 6am), either short frequent wakings or a long one (“split night”)
+ Wakes at 5am and can’t fall back asleep, even with help
Why This Matters
Understanding whether your baby is overtired or undertired is one of the keys to figuring out the right nap lengths, wake windows, and bedtime. The truth is, your baby might not need a drastic overhaul — just a few schedule tweaks to get things back on track.
And no, you don’t have to figure that all out on your own! We would love to help you! Check out our services here!
Want Help with Your Baby’s Schedule?
If you're constantly playing the “is it too much sleep… or not enough?” game, my Ultimate Baby Sleep Schedule Guide is for you. It breaks down wake windows and ideal schedules by age — so you can stop guessing and start sleeping.
Or, if you want one-on-one personalized help for YOUR baby, we are here for that too! Let us take the guesswork out of baby sleep and just get you guys sleeping! Email us today, sleep better soon!