4-Month Milestones: What Your Baby Can Do Now

At four months, babies seem to “wake up” to the world. They laugh at your silly faces, grab at everything and push up during tummy time like tiny athletes. This guide covers the 4-month milestones your baby may be reaching now, what changes with sleep and feeding, simple ways to play together and when to check in with your pediatrician.

4-month milestones checklist (CDC)

These are the CDC’s milestones for 4 months, grouped by area. Check them off as you see them.

Social and emotional

• Smiles on their own to get your attention.
• Chuckles (not yet a full laugh) when you try to make them laugh.
• Looks at you, moves or makes sounds to get or keep your attention.

Language and communication

• Makes cooing sounds like “oooo” and “aahh.”
• Makes sounds back when you talk.
• Turns the head toward the sound of your voice.

Cognitive (learning and problem-solving)

• If hungry, opens the mouth when seeing the breast or bottle.
• Looks at their hands with interest.

Movement and physical

• Holds the head steady without support when you hold them.
• Holds a toy when you put it in their hand.
• Uses an arm to swing at toys.
• Brings hands to the mouth.
• Pushes up onto elbows or forearms when on the tummy.

Looking back? Compare with our 3-month milestones guide, or see the whole first year in our baby milestones month-by-month guide.

Other skills you may notice around 4 months

Beyond the checklist, many parents see these changes over the next few weeks:

• First rolls, usually from tummy to back. Read more about when babies roll over.
• Real belly laughs that follow the early chuckles.
• Reaching with both hands and grabbing your hair, glasses or earrings.
• Lots of drool and chewing on fists. This is common and doesn’t always mean a tooth is coming.
• Bearing weight on the legs when you hold them upright on your lap.
• More curiosity than ever, which can make feeds distracted.

Sleep at 4 months (and the “4-month sleep regression”)

The American Academy of Sleep Medicine recommends 12 to 16 hours of sleep every 24 hours, including naps, for babies 4 to 12 months old. Around this age, many babies who slept well suddenly wake more often. Parents call it the 4-month sleep regression; in reality, sleep cycles are maturing to look more like adult sleep.

• Keep a consistent, short bedtime routine: bath, feed, book, song.
• Put your baby down drowsy but awake, so they practice falling asleep.
• Follow safe sleep every time: on the back, on a firm, flat surface with no pillows, bumpers or loose blankets, as the AAP recommends.
• Stop swaddling once your baby shows signs of trying to roll; a wearable blanket is a safe option.

Feeding at 4 months

The American Academy of Pediatrics recommends breast milk (or formula) alone for about the first 6 months. Your 4-month-old may watch you eat with great interest; however, that alone doesn’t mean they’re ready for solids. Readiness signs include sitting with support, good head control and moving food to the back of the mouth instead of pushing it out. If you’re wondering whether to start earlier, ask your pediatrician.

Play ideas for a 4-month-old

1. Tummy time with a view. Lie face to face or place a baby-safe mirror in front of them. Short, frequent sessions add up.
2. Reach and grab. Hold a rattle just within reach and let them swipe at it.
3. Back-and-forth “conversations.” Copy their coos, pause and wait for a reply.
4. Silly faces and peekaboo. Your face is still their favorite toy.
5. Texture time. Let them touch a soft brush, a crinkly cloth and a smooth wooden ring.
6. Read and sing. High-contrast board books, nursery rhymes and songs with hand motions.

The 4-month checkup

Your baby’s 4-month well visit usually includes a weight, length and head measurement, a physical exam, a developmental check and the next round of routine vaccines. It’s also a good time to ask about sleep, feeding and starting solids. Bring the milestones you’ve noticed, along with any questions you’ve jotted down.

When to talk to your pediatrician

Every baby develops at their own pace, but the CDC encourages parents to act early. Talk to your baby’s doctor if, around 4 months, your baby:

• Doesn’t watch things as they move or doesn’t smile at people.
• Can’t hold the head steady when held.
• Doesn’t coo or make sounds, or doesn’t react to loud sounds.
• Doesn’t bring things to the mouth or push down with the legs when feet are on a firm surface.
• Seems very stiff or very floppy, or loses skills they used to have.

You can also contact your state’s early intervention program for a free evaluation; you don’t need a referral.

This guide is for general information and doesn’t replace advice from your pediatrician.

Capture this stage before it changes

Four months is full of firsts that pass in a blink: the first belly laugh, the first roll, the way they grab your finger. Record a short video of a laughing session, take the monthly photo in the same spot and write down the sounds they make right now. Next up: the 6-month-old milestones.

Sources

This guide summarizes public guidance from the CDC and the American Academy of Pediatrics (AAP). The milestone lists come from these sources; the activity and memory ideas are our own suggestions. This article has not been reviewed by a clinician and doesn’t replace your pediatrician’s advice. Last reviewed: November 1, 2026.

• CDC — Milestones by 4 months
• AAP (HealthyChildren.org) — Movement milestones: babies 4 to 7 months
• AAP (HealthyChildren.org) — Back to sleep, tummy to play

Frequently asked questions