Boys growth chart percentile calculator
Enter your daughter’s or son’s date of birth and a weight, length or head circumference to see where it falls on the WHO growth chart for boys. No account needed, and nothing you type leaves your browser.
Enter a date of birth and at least one measurement to see the percentile.
WHO medians for boys
The 50th percentile at common checkup ages. Half of healthy boys measure more and half less.
| Age | Weight | Length | Head |
|---|---|---|---|
| Birth | 3.3 kg / 7.4 lb | 49.9 cm / 19.6 in | 34.5 cm / 13.6 in |
| 3 months | 6.4 kg / 14.1 lb | 61.4 cm / 24.2 in | 40.5 cm / 16.0 in |
| 6 months | 7.9 kg / 17.5 lb | 67.6 cm / 26.6 in | 43.3 cm / 17.1 in |
| 9 months | 8.9 kg / 19.6 lb | 72.0 cm / 28.3 in | 45.0 cm / 17.7 in |
| 1 year | 9.6 kg / 21.3 lb | 75.7 cm / 29.8 in | 46.1 cm / 18.1 in |
| 18 months | 10.9 kg / 24.1 lb | 82.3 cm / 32.4 in | 47.4 cm / 18.7 in |
| 2 years | 12.2 kg / 26.8 lb | 87.8 cm / 34.6 in | 48.3 cm / 19.0 in |
Full month-by-month tables with the 3rd to 97th percentiles: weight chart, length chart, head circumference chart.
Reading the result
A percentile compares one measurement with boys of the same age. Anything between the 3rd and the 97th percentile is within the usual range on the WHO chart, and a steady position on the curve matters more than the number itself.
Pediatricians pay closer attention when a measurement is below the 2.3rd or above the 97.7th percentile, or when the curve crosses two of the main percentile lines over a few months. More in What percentile should my baby be?
Common questions
What percentile is normal on a boys growth chart?
Any percentile inside the chart's range can be normal. For children under 2, the CDC suggests the WHO chart's 2nd and 98th percentile lines as the points where a doctor takes a closer look. A boy who stays near the same percentile line from visit to visit is growing steadily, whether that line is the 10th or the 90th.
What is a normal weight for a 6-month-old boy?
On the WHO standard, the 3rd to 97th percentile at 6 months runs from 6.4 kg (14.2 lb) to 9.7 kg (21.4 lb), with a median of 7.9 kg (17.5 lb).
What is a normal length for a 1-year-old boy?
On the WHO standard, the 3rd to 97th percentile at 12 months runs from 71.3 cm (28.1 in) to 80.2 cm (31.6 in), with a median of 75.7 cm (29.8 in).
Why are there separate growth charts for boys and girls?
Boys are on average a little heavier and longer than girls from birth, so each sex has its own chart. Comparing a child with the right chart gives a more accurate percentile.
Is this calculator the WHO or the CDC chart?
Both. It uses the WHO Child Growth Standards by default (birth to 5 years) and lets you switch to the CDC infant charts (birth to 36 months). The CDC recommends WHO charts for children under 2 in the United States.
Keep the whole curve
Growthling saves every checkup and plots it on the WHO or CDC chart for boys, with the percentile for each one. Free to sign up.
Start tracking freeLooking for girls? Girls growth chart percentile calculator.
Sources: WHO Child Growth Standards and CDC growth charts. For information only; not medical advice.