Free guide
Developmental Milestone Checklist: Birth to Three
What most children can do at each age from two months to three years, and the signs worth acting on. Free to print, no sign-up.
- Expert Reviewed
- Evidence Based
- Free, No Sign-Up
This is a printable checklist of what most children can do by each age from two months to three years, alongside the signs worth mentioning to a doctor. It follows the CDC's developmental milestone checklists, revised in 2022 to describe what most children can do at a given age rather than what half can, so ages here may differ from older charts. A single missed milestone is usually not the concern. What matters is a pattern: several delays together, difficulty across more than one area, or a skill a child previously had and lost. If something concerns you, evaluation is free for children under three in the United States and a parent can arrange it without a doctor's referral.
What this checklist is
A printable list of what most children can do at each age from two months to three years, next to the signs worth mentioning to a doctor. It is a conversation starter for an appointment, not a test and not a diagnosis.
It follows the CDC's developmental milestone checklists, and the same rows appear on our milestones and red flags page, on baby development and on toddler development. Checked August 17, 2026.
How to use it
These are guides, not deadlines. Children arrive at the same skills across a wide range of ages, and healthy development is uneven by nature.
Check the band your child is in now, rather than reading ahead. A single late item is usually not the concern. A pattern is: several things behind at once, difficulty across more than one area, or a skill that has been lost.
Milestones and red flags by age
The left column is what most children do by each age. The right column is not a deadline; it is a prompt to raise something at your next visit.
| By this age | Most children can | Worth asking about if not |
|---|---|---|
| 2 months |
|
|
| 4 months |
|
|
| 6 months |
|
|
| 9 months |
|
|
| 1 year |
|
|
| 15 months |
|
|
| 18 months |
|
|
| 2 years |
|
|
| 30 months |
|
|
| 3 years |
|
|
What if my child is behind on one thing?
Usually nothing, and this is the question the checklist exists to answer. Development is not a single track that a child is ahead of or behind on. Children work on one area at a time, and it is ordinary for one to stall while another surges - a baby learning to walk frequently pauses on new words, and a toddler in the middle of a language burst may leave climbing alone for a month.
What changes the picture is a pattern. Several items behind at once, difficulty that crosses more than one area, or a gap that is widening rather than closing over a few months. Those are worth raising, and raising them costs nothing.
What changes it immediately is a skill that has gone backward. A child who was babbling and has stopped, who was walking and no longer is, or who made eye contact and now does not, should be seen by a doctor promptly rather than watched for another few weeks. Losing an acquired skill is investigated differently from being slow to gain one.
What if my child was born early?
Use corrected age, not actual age. Corrected age adjusts for how early your baby arrived: a baby born two months before their due date is generally compared with babies two months younger, so an eight-month-old born two months early is assessed against six-month milestones.
This matters most in the first year, when two months is a large share of a baby's life, and matters less as a child gets older. Most clinicians stop adjusting somewhere in the second or third year, and your pediatrician can tell you when that applies to your child. If you are using this checklist for a premature baby, write both ages at the top so nobody reading it has to guess which you meant.
What to do if something concerns you
Under three, contact your state's early intervention program directly. A parent can refer their own child - no doctor's referral, no diagnosis, and no income requirement to be evaluated. The evaluation is free everywhere in the United States; what services cost afterward depends on the state. There is a legal timeline once you make contact, so ask for the date when you call.
Three and over, the route runs through your school district. Request the evaluation in writing - that is what starts the legal timeline, and a conversation at pickup does not. See our school evaluation letter template.
At any age, private therapy is available and does not depend on qualifying for school services. And whichever route you take, bring specific examples with rough dates, and bring video if you have it.
Frequently asked questions
Are these the same milestones my pediatrician uses?
They follow the CDC's checklists, which were revised in 2022 and are widely used in developmental surveillance. Some practices also use a formal screening questionnaire at set visits. If your pediatrician's chart differs from an older one you have seen, the 2022 revision is usually why.
Why did the ages change from the chart I had before?
The 2022 revision moved the checklists to describing what most children can do at a given age rather than what about half can. That raised some ages and removed items that were too variable to be useful, and it is why an older chart may show a skill earlier than this one does.
Does a missed milestone mean my child has a diagnosis?
No. The checklist is a prompt to ask, not a test with a pass mark. Most children who are late on one item are simply on the later end of a wide normal range. What is worth raising is a pattern, or a skill that has gone backward.
Can I use this for a child born prematurely?
Yes, but compare against corrected age rather than the date on the birth certificate. A baby born two months early is usually assessed alongside babies two months younger. Your pediatrician can tell you how long the adjustment applies.
Is the PDF really free?
Yes. No email, no account, no form. Print it, put it on the fridge, take it to an appointment, or send it to someone else who needs it. It carries our name and address, which is the only thing we get from it.
What if my child is older than three?
This checklist stops at three because that is where the route to help changes. From three, evaluation runs through your school district rather than early intervention, and it needs a written request.
More free guides
Want the next one?
We send occasional guides and plain-English explainers for parents. Entirely optional, and nothing here was hidden behind it.