Newborn Head Circumference: Normal Range + WHO Head Circumference Chart

The normal head circumference of a newborn is 34.5 cm for boys and 33.9 cm for girls — those are the median (50th percentile) values from the WHO Child Growth Standards. By the first birthday, the median rises to 46.1 cm for boys and 44.9 cm for girls.

But a single number tells you very little on its own. Your baby's head circumference is only meaningful when you read it against the chart for their age and sex, and when you look at how it changes over successive visits. Below you'll find the complete month-by-month head circumference chart — boys first, then girls — plus how to measure correctly at home, what the 3rd and 97th percentile lines actually mean, and the red flags that genuinely warrant a paediatrician's opinion.

Source: WHO Child Growth Standards (2006), Head circumference-for-age, birth to 5 years, percentile tables for boys and girls. World Health Organization

Why Head Circumference Is Measured at Every Visit

Head circumference — technically the occipito-frontal circumference or OFC — is the simplest, cheapest proxy your paediatrician has for brain growth. The skull grows because the brain inside it grows. A head that is tracking steadily along its own curve is reassuring evidence that the brain underneath is developing normally.

That is why it sits alongside weight and length at every well-baby check, and why doctors care far more about the shape of the line over time than about any single reading.

Head Circumference Chart for Baby Boys (0–24 Months)

All values in centimetres, transcribed from the official WHO percentile tables.

Head Circumference Chart for Baby Girls (0–24 Months)

A note on the 3rd percentile: it is close to, but not the same as, −2 SD — the cut-off doctors actually use for microcephaly. Your paediatrician calculates the exact figure. Please don't diagnose anything from this table.

Head Circumference Chart by Age: 2–5 Years

Notice the pattern across every table: boys' heads run roughly 0.5–1.2 cm larger than girls' at the same age. Always read your baby's number against the chart for their sex — using the wrong column is one of the most common reasons parents panic unnecessarily.

What Is the Normal Head Circumference Range for a Newborn?

For a healthy full-term baby, the normal head circumference range at birth sits roughly between:

• Boys: 32.1 cm – 36.9 cm
• Girls: 31.7 cm – 36.1 cm

That span is the 3rd to 97th percentile. Ninety-four out of every hundred healthy babies fall inside it. The remaining six — three at each end — are also, in most cases, perfectly healthy. Percentiles are a description of where a baby sits in the population, not a pass/fail line.

How to Measure Your Baby's Head Circumference Correctly

Getting the technique right matters more than most parents realise. A badly taken measurement is by far the most common source of a false alarm at home.

1. Use a non-stretchable tape. A cloth or stretched-out tailor's tape is the number one cause of a wrong reading. A paper or plastic measuring tape is what you want.
2. Find the widest point. Run the tape around the forehead, just above the eyebrows and above the ears, and over the most prominent bump at the back of the head.
3. Measure three times, take the largest. Small shifts in tape position change the number by several millimetres.
4. Read to the nearest 0.1 cm.

Two things that trip parents up

Premature babies must be plotted on corrected age, not birth age. A baby born eight weeks early and now twelve weeks old is plotted at four weeks. Using birth age will make their head look alarmingly small when it isn't.

A head measured in the first day or two of life often reads low. Moulding during birth and caput (scalp swelling) temporarily squeeze the skull. It rounds out over the first week, which is why the one-week measurement can look like a sudden jump. That jump is normal and expected.

What If My Baby's Head Is Small? (Microcephaly)

Three things worth holding onto:

• A single measurement below the 3rd percentile is not a diagnosis. By the mathematical definition of a percentile, roughly 3 in 100 completely healthy babies sit below that line. Someone has to.
• The trend matters more than any one point. A baby tracking steadily along the 5th percentile is usually fine. A baby who crosses down from the 50th to the 5th over successive visits is a different situation.
• Context matters. Head circumference below the 3rd percentile together with developmental delay, poor feeding, or missed milestones should be assessed by a paediatrician.

What If My Baby's Head Is Large? (Macrocephaly)

The same logic applies in reverse. A single reading above the 97th percentile is not a diagnosis — again, about 3 in 100 healthy babies live up there. And many big-headed babies simply have big-headed parents. This is called benign familial macrocephaly, and it is common enough that your paediatrician will often measure your head as part of the assessment.

What needs review is a baby who crosses upward — from the 50th to above the 97th — over successive visits.

Red Flags: When to See a Doctor

Book a paediatric review if you notice:

• Head circumference crossing percentile lines in either direction over successive visits (50th down to the 10th, or 50th up past the 97th)
• Head size increasing rapidly, or growing much faster than length and weight
• A bulging, tense or firm fontanelle when your baby is calm and held upright — this can signal raised pressure inside the skull
• A fontanelle that is sunken (often dehydration) or that closes very early
• Head circumference below the 3rd percentile plus developmental delay, poor feeding, or missed milestones
• Any reading below the 3rd or above the 97th percentile — get it confirmed properly rather than self-diagnosing from a home tape

WHO or IAP — Which Head Circumference Chart Should Indian Parents Use?

For children under 5 years, the WHO Child Growth Standards are the correct chart to use in India.

The Indian Academy of Pediatrics (IAP) endorses the WHO 2006 standards for the 0–5 year age group, and these are what India's national growth monitoring uses — including the Mother and Child Protection (MCP) Card you were given at the hospital.

There's a good reason for this. The WHO standards are prescriptive rather than descriptive: they describe how children should grow under optimal nutrition and care, rather than how an average population happens to be growing. And the WHO Multicentre Growth Reference Study that produced them included an Indian site (Delhi), which is part of why they're considered applicable to Indian children.

IAP's own growth charts (revised 2015) cover ages 5–18 years, and only for height, weight and BMI — they do not include head circumference at all. So there is no "IAP head circumference chart" for babies. For head circumference in the under-fives, WHO is the standard in India and everywhere else.

Frequently Asked Questions

My baby's head circumference is in the 95th percentile — should I be worried?

Not necessarily. The 95th percentile simply means your baby's head is larger than 95% of babies the same age and sex. If your baby has always been around this percentile and is meeting developmental milestones, this is most likely just their normal build. Family history of larger heads plays a real role. Your paediatrician will watch the growth pattern, not one measurement.

My baby's head is below the 3rd percentile — does that mean microcephaly?

Not on its own. A single reading below the 3rd percentile is not a diagnosis — around 3 in 100 healthy babies sit below it purely by definition. What matters is the trend over time, and whether your baby is feeding well and hitting milestones. Have it confirmed at a clinic with a proper non-stretchable tape rather than acting on a home measurement.

When does the soft spot (fontanelle) close?

The front soft spot typically closes between 9 and 18 months. The smaller one at the back usually closes by 2–3 months. The soft spot exists to allow rapid brain growth and is protected by a tough membrane, so gentle touching and washing during normal care is completely safe. Contact your paediatrician if it is persistently bulging, very sunken, or closes much earlier or later than expected.

How often should head circumference be measured?

At every well-baby visit — typically at birth, 1 week, 1 month, 2 months, 4 months, 6 months, 9 months, 12 months, 15 months, 18 months and 24 months. After age two, measurements become less frequent unless there is a specific concern.

Mera baby ka sir bada lag raha hai — is this normal?

In most cases, yes. Plenty of babies have heads that look large in proportion to their bodies, and it is very often simply genetic. What matters is whether the head is growing at a consistent rate along its own curve on the chart. If it's following the same percentile line visit after visit, there is usually nothing to worry about.

Will my baby's flat-looking head shape become normal?

Positional flattening (plagiocephaly) is very common and usually improves once babies start sitting up and spending less time lying on their backs. Tummy time and repositioning help, and in more pronounced cases a moulding helmet is sometimes used. Most babies' heads round out well by age 1–2.

Does head circumference predict intelligence?

No. Within the normal range, head size has no meaningful relationship to how clever your child will be. Head circumference is a screening tool for growth problems, not a measure of ability.

The Short Version

• Normal head circumference at birth: 34.5 cm (boys), 33.9 cm (girls) at the median; roughly 31.7–36.9 cm across the normal range.
• Use the chart for your baby's sex, and use corrected age for premature babies.
• Trend beats snapshot. One point below the 3rd or above the 97th percentile is not a diagnosis. Crossing percentile lines over successive visits is what needs attention.
• Measure with a non-stretchable tape, three times, take the largest.
• A bulging fontanelle with vomiting, drowsiness or seizures is an emergency — call 112 or 108.

This article is general information and is not a substitute for advice from your paediatrician. If you are worried about your baby's head size or growth, please have them examined. In an emergency, call 112 or 108.