Baby percentile calculator
Where does your child's weight and height sit among children the same age? See it in seconds on the WHO growth curves.
Enter the date of birth and a weight or height measurement, then select Calculate.
Average weight and length by month (WHO)
The median is the value half of children fall below and half above; the normal range runs from the 3rd to the 97th percentile. What matters is your child's own curve over time, not a single measurement.
| Age | Weight (kg) | Height (cm) | ||
|---|---|---|---|---|
| Median | Normal range | Median | Normal range | |
| 0 months | 3.2 | 2.4–4.2 | 49.1 | 45.6–52.7 |
| 1 month | 4.2 | 3.2–5.4 | 53.7 | 50.0–57.4 |
| 2 months | 5.1 | 4.0–6.5 | 57.1 | 53.2–60.9 |
| 3 months | 5.8 | 4.6–7.4 | 59.8 | 55.8–63.8 |
| 4 months | 6.4 | 5.1–8.1 | 62.1 | 58.0–66.2 |
| 5 months | 6.9 | 5.5–8.7 | 64.0 | 59.9–68.2 |
| 6 months | 7.3 | 5.8–9.2 | 65.7 | 61.5–70.0 |
| 7 months | 7.6 | 6.1–9.6 | 67.3 | 62.9–71.6 |
| 8 months | 7.9 | 6.3–10.0 | 68.7 | 64.3–73.2 |
| 9 months | 8.2 | 6.6–10.4 | 70.1 | 65.6–74.7 |
| 10 months | 8.5 | 6.8–10.7 | 71.5 | 66.8–76.1 |
| 11 months | 8.7 | 7.0–11.0 | 72.8 | 68.0–77.5 |
| 12 months · 1 year | 8.9 | 7.1–11.3 | 74.0 | 69.2–78.9 |
| 15 months | 9.6 | 7.7–12.2 | 77.5 | 72.4–82.7 |
| 18 months | 10.2 | 8.2–13.0 | 80.7 | 75.2–86.2 |
| 21 months | 10.9 | 8.7–13.8 | 83.7 | 77.9–89.4 |
| 24 months · 2 years | 11.5 | 9.2–14.6 | 85.7 | 79.6–91.8 |
| 30 months | 12.7 | 10.1–16.2 | 90.7 | 84.0–97.3 |
| 36 months · 3 years | 13.9 | 11.0–17.8 | 95.1 | 87.9–102.2 |
| 42 months | 15.0 | 11.8–19.5 | 99.0 | 91.4–106.7 |
| 48 months · 4 years | 16.1 | 12.5–21.1 | 102.7 | 94.6–110.8 |
| 54 months | 17.2 | 13.2–22.8 | 106.2 | 97.6–114.7 |
| 60 months · 5 years | 18.2 | 14.0–24.4 | 109.4 | 100.5–118.4 |
| Age | Weight (kg) | Height (cm) | ||
|---|---|---|---|---|
| Median | Normal range | Median | Normal range | |
| 0 months | 3.3 | 2.5–4.3 | 49.9 | 46.3–53.4 |
| 1 month | 4.5 | 3.4–5.7 | 54.7 | 51.1–58.4 |
| 2 months | 5.6 | 4.4–7.0 | 58.4 | 54.7–62.2 |
| 3 months | 6.4 | 5.1–7.9 | 61.4 | 57.6–65.3 |
| 4 months | 7.0 | 5.6–8.6 | 63.9 | 60.0–67.8 |
| 5 months | 7.5 | 6.1–9.2 | 65.9 | 61.9–69.9 |
| 6 months | 7.9 | 6.4–9.7 | 67.6 | 63.6–71.6 |
| 7 months | 8.3 | 6.7–10.2 | 69.2 | 65.1–73.2 |
| 8 months | 8.6 | 7.0–10.5 | 70.6 | 66.5–74.7 |
| 9 months | 8.9 | 7.2–10.9 | 72.0 | 67.7–76.2 |
| 10 months | 9.2 | 7.5–11.2 | 73.3 | 69.0–77.6 |
| 11 months | 9.4 | 7.7–11.5 | 74.5 | 70.2–78.9 |
| 12 months · 1 year | 9.6 | 7.8–11.8 | 75.7 | 71.3–80.2 |
| 15 months | 10.3 | 8.4–12.7 | 79.1 | 74.4–83.9 |
| 18 months | 10.9 | 8.9–13.5 | 82.3 | 77.2–87.3 |
| 21 months | 11.5 | 9.3–14.3 | 85.1 | 79.7–90.5 |
| 24 months · 2 years | 12.2 | 9.8–15.1 | 87.1 | 81.4–92.9 |
| 30 months | 13.3 | 10.7–16.6 | 91.9 | 85.5–98.3 |
| 36 months · 3 years | 14.3 | 11.4–18.0 | 96.1 | 89.1–103.1 |
| 42 months | 15.3 | 12.2–19.4 | 99.9 | 92.4–107.3 |
| 48 months · 4 years | 16.3 | 12.9–20.9 | 103.3 | 95.4–111.2 |
| 54 months | 17.3 | 13.6–22.3 | 106.7 | 98.4–115.0 |
| 60 months · 5 years | 18.3 | 14.3–23.8 | 110.0 | 101.2–118.7 |
Weight in kg, length/height in cm. Length is measured lying down up to 24 months, then standing (WHO rule).
Curves are calculated from the WHO Child Growth Standards tables (0 to 5 years).
This tool does not diagnose and gives no medication or feeding advice. The calculation uses the L, M and S values from the WHO Child Growth Standards tables (0 to 5 years), smoothed linearly between whole months. Children born preterm, twins and children with a chronic condition need a doctor's assessment.
About this tool
What is a percentile and what does this tool do?
A percentile compares your child with 100 children of the same age and sex. The 40th percentile means about 40 of those children are below that measurement. A high or low percentile is not good or bad on its own; what matters is that a child keeps following their own curve. This tool uses the WHO Child Growth Standards for ages 0 to 5 to work out the percentile for weight and height and shows where your child sits on the curve.
How to use it
Choose the sex, enter the date of birth and the date of the measurement, then the weight in kilograms and the height in centimetres. Children under two are measured lying down and older children standing; if you measured the other way, pick the matching button and the tool applies the WHO correction of 0.7 cm. Select Calculate to see the result; calculation runs in your browser.
How to read the result
One measurement is a snapshot, not the whole film. Healthy growth shows up as a child staying close to their own curve over the months. If the curve drifts clearly up or down across several measurements, or the result is below the 3rd or above the 97th percentile, speak to your doctor. Babies born early or with a low birth weight need an age correction, which your doctor applies.
Limits and source
This tool does not diagnose and gives no medication or feeding advice. The calculation uses the L, M and S values from the WHO Child Growth Standards tables (0 to 5 years), smoothed linearly between whole months. Children born preterm, twins and children with a chronic condition need a doctor's assessment.
How can I assess the height and weight of a 3-year-old girl?
A single measurement does not diagnose a condition. Select Girl, enter the child's date of birth and measurement date, then enter weight and/or height and press Calculate. Height-for-age and weight-for-age percentiles are shown separately. Review the result alongside earlier measurements and with the health professional who follows your child.
