Check where your baby's weight and length sit on WHO growth charts. For children aged 0–24 months.
A percentile shows where your baby sits compared to other babies of the same age and sex. For example, the 50th percentile means your baby weighs the same as or more than 50% of babies that age — right in the middle.
There is a wide range of "normal." A baby on the 15th percentile is not underweight — they're just smaller than average. Similarly, a baby on the 85th percentile is not necessarily overweight. What matters most is that your baby follows their own growth curve consistently over time.
See your child health nurse or GP if: weight or length drops across two or more percentile lines, weight is below the 3rd percentile or above the 97th, your baby isn't gaining weight over a period of weeks, you have any concerns about feeding or growth, or your baby seems unwell or isn't reaching developmental milestones.