Baby Milestones: Month-by-Month Development (0-12 Months)
What to expect in your baby's first year — smiling, rolling, sitting, crawling, first words and steps — plus the developmental checks and when to raise a concern.
In a nutshell
- Milestones are ranges, not deadlines — babies develop at their own pace, and a wide spread of timing is completely normal.
- Rough first-year arc: social smile ~6-8 weeks; rolling ~4-6 months; sitting ~6-9 months; crawling ~7-10 months; first words + steps around 12 months.
- Use corrected age for babies born prematurely (count from the due date, not the birth date) for at least the first 2 years.
- Development spans five areas: gross motor, fine motor, language, social/emotional and cognitive — watch the whole picture, not one skill.
- Tell your health visitor or GP if your baby loses skills, isn't responding to sound, isn't smiling by ~8 weeks, or you have any niggling concern — earlier support is always better.
How to read milestones (without the worry)
Milestones describe the typical age range by which most babies develop a skill — they're a guide, not a scoreboard. A baby who's a little 'behind' on one thing is often racing ahead on another. What matters most is steady forward progress over time and the overall picture across all areas of development.
0-3 months
- Gross motor: lifts head briefly during tummy time; movements become smoother.
- Fine motor: hands start to open; briefly grasps a finger or object.
- Language: coos and gurgles; quietens or turns to familiar voices.
- Social: the first real social smile (around 6-8 weeks) — a huge moment; makes eye contact.
Daily tummy time (a few minutes, several times a day, supervised and awake) builds the neck and shoulder strength behind almost every later milestone.
4-6 months
- Gross motor: rolls (often back-to-front first, then both ways); good head control; may start to sit with support.
- Fine motor: reaches for and grabs objects; brings hands and toys to the mouth.
- Language: babbles ('ba', 'ga'), laughs, and responds to their name emerging.
- Social: enjoys faces and mirrors, shows clear delight at familiar people.
Around 6 months, many babies show signs of readiness for solid food — see our Starting Solids guide for the readiness signs (it's about development, not just age).
7-9 months
- Gross motor: sits unsupported; may start to crawl, bottom-shuffle or commando-crawl; might pull to stand.
- Fine motor: passes objects between hands; develops the pincer grasp (thumb + finger) for picking up small bits.
- Language: babbles tunefully ('mama', 'dada' non-specifically), understands 'no' and simple words.
- Social: separation anxiety and stranger wariness often begin — a normal sign of attachment.
10-12 months
- Gross motor: pulls up, cruises along furniture, may stand alone and take first steps (anywhere from ~9-15 months).
- Fine motor: refined pincer grasp; bangs objects together; starts to feed themselves finger foods.
- Language: first meaningful words; understands far more than they can say; waves 'bye-bye', claps.
- Social: plays simple games (peekaboo), points at things, copies you.
When to raise a concern
Routine reviews (e.g. the health-visitor checks and the 9-12 month and 2-2.5 year assessments) are there to catch concerns — bring any worries, however small.
Frequently asked questions
When do babies start smiling, rolling, sitting and walking?
As a rough guide: social smile ~6-8 weeks, rolling ~4-6 months, sitting unsupported ~6-9 months, crawling ~7-10 months, and first steps around 9-15 months. These are ranges — wide variation is normal.
What if my baby is 'behind' on a milestone?
Milestones are ranges, not deadlines, and babies often lead in one area while taking longer in another. Look at steady overall progress. If you're worried, or if your baby loses a skill, check with your health visitor.
How do milestones work for premature babies?
Use corrected age — count from the original due date, not the birth date — for at least the first two years. A baby born early is developmentally 'younger' than their calendar age.
Is it normal for my baby not to crawl?
Yes — some babies skip crawling entirely and go straight to bottom-shuffling, cruising or walking. What matters is that they're finding ways to move and progress.
When should I worry about development?
If your baby loses skills, isn't smiling by ~8 weeks, doesn't respond to sound, doesn't make eye contact, has very stiff or floppy muscles, or isn't babbling/pointing by ~12 months — speak to a professional. Earlier help is better.
Does more 'stimulation' make my baby develop faster?
Babies mainly need responsive interaction, talking, reading, tummy time and safe space to move and explore — not flashcards or screens. Everyday loving interaction is the best developmental tool.
Do screens help or harm development?
Major guidelines advise avoiding screen time for under-18-month-olds (other than video calls). Real-life interaction and play support language and learning far better at this age.
Sources
More guides
Baby Sleep: Schedules, Regressions & Gentle Settling
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Newborn Care: Your Complete First 6 Weeks Guide
Feeding, nappies, the umbilical cord, bathing, soothing a crying baby, and the health checks and red flags every new parent needs in the fourth trimester.
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Starting Solids: The Complete Weaning Guide
When and how to start solids, purées vs baby-led weaning, first foods, the allergen rules, foods to avoid, and how to wean safely while keeping milk as the main drink.
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Educational only — not medical advice. Always consult your midwife, GP or paediatrician for personalised guidance. Medical disclaimer.