Baby milestones checklist by month

Enter your child's date of birth. If your baby was born before 37 weeks, also enter the week of birth: until age 2, the tool uses corrected age. It then shows your child's age and opens the most recent checklist your child has reached, marked with a dot. You can switch to any other age: 2, 4, 6, 9, 12, 15 and 18 months, 2 years, 30 months, and 3, 4 and 5 years.

Each checklist is grouped into four areas, as on the CDC lists:

• Social/Emotional
• Language/Communication
• Cognitive (learning, thinking, problem-solving)
• Movement/Physical Development

Tick each milestone you've seen your child do, and the counter shows how many of the list's items are checked. Below the list, a short box sums up when to talk to the doctor.

Everything runs in your browser. Your checkmarks are saved only in this browser's local storage, so they'll still be there next time, unless you clear your browsing data.

The milestones come word for word from the CDC's Learn the Signs. Act Early. checklists. The current lists cite a 2022 Pediatrics article, "Evidence-Informed Milestones for Developmental Surveillance Tools."

The key detail is the bar they use. According to the CDC, each checklist includes milestones that most children (75% or more) are expected to reach by that age. They're not averages; they're things most children can already do. So if your child isn't doing one of them yet, that's a good reason to check in with the doctor rather than wait and see.

It also means a single missing item isn't a diagnosis. Children develop at their own pace, and the checklist is a tool for watching development and starting a conversation, not a screening test.

A few examples from each CDC checklist (the full lists are in the tool):

Age	Examples of milestones
2 months	Smiles when you talk or smile; holds head up on tummy
4 months	Coos ("oooo", "aahh"); holds head steady when held
6 months	Laughs; rolls from tummy to back
9 months	Looks when you call their name; sits without support
1 year	Waves "bye-bye"; pulls up to stand
15 months	Tries to say one or two words besides "mama" or "dada"; takes a few steps alone
18 months	Tries to say three or more words besides "mama" or "dada"; walks without holding on
2 years	Says at least two words together, like "More milk"; kicks a ball
30 months	Says about 50 words; jumps with both feet

You'll notice crawling isn't on the list. It isn't one of the CDC checklist milestones; instead the lists look at sitting, pulling up to stand and walking.

A baby born at 32 weeks is now 10 months old by the calendar. She arrived 8 weeks before her due date, so the tool subtracts 8 weeks and shows a corrected age of about 8.1 months. It opens the 6-month checklist, because that's the most recent one she has reached by corrected age. The 9-month list opens once her corrected age is close to 9 months.

You can still open the 9-month list to see what's coming next. If she's already doing some of those things, great. If she isn't yet, that's expected for her corrected age. Corrected age is used until age 2; after that, the tool uses her actual age.

Growth works the same way: the baby growth percentile calculator also corrects for early birth.

Talk to your child's doctor if:

• your child isn't meeting one or more milestones for their age
• your child loses skills they once had, for example no longer says words they used to say
• anything about how your child plays, learns, speaks, acts or moves concerns you

You don't need to wait for the next well-child visit; ask for an appointment sooner. Bring the checklist and ask whether a developmental screening makes sense. Checking early rather than waiting is the whole idea behind the CDC's Act Early message.

For everyday questions at this stage, try the baby sleep schedule or the teething chart.

This checklist isn't a developmental screening test or a diagnosis, and it isn't a substitute for medical advice.