Child Growth Chart Calculator
Use one dated measurement to calculate CDC height-for-age, weight-for-age, or both for children from the second birthday through the day before the 20th birthday. BMI-for-age is also calculated when both height and weight are entered.
Results are age- and sex-specific reference comparisons for one measurement date. They are not diagnoses or growth trends.
Have a child under 2? Use the WHO Baby Growth Calculator.
What the three results answer
All three are age- and sex-specific CDC comparisons, but they do not measure the same thing. Use this comparison to choose the result and follow-up resource that match your question.
- Height-for-age
Inputs used: Standing height, exact age, and the selected sex chart.
Question answered: Where does the child’s current stature fall in the CDC reference?
What it does not answer: It does not describe weight status or predict adult height.
Best next resource: Understand height percentile
- Weight-for-age
Inputs used: Weight, exact age, and the selected sex chart.
Question answered: Where does the child’s current body weight fall in the CDC reference?
What it does not answer: It does not adjust for height or classify weight status.
Best next resource: Understand weight percentile
- BMI-for-age
Inputs used: Standing height, weight, exact age, and the selected sex chart.
Question answered: Where does BMI fall in the CDC reference, and which screening category applies?
What it does not answer: It does not diagnose a condition or directly measure body fat.
Best next resource: Understand BMI percentile
Working from a printed chart? Review how to follow CDC chart axes and percentile curves.
Why three percentiles can be different
Height-for-age uses height, weight-for-age uses weight, and BMI-for-age relates weight to height. Each value is located in a different reference distribution, so the percentile numbers do not need to match. Different results do not mean the calculations conflict.
In the worked example below, the height percentile is higher than the weight percentile, while the BMI percentile is lower than both. That pattern simply reflects three different comparisons; this page does not infer a diagnosis, body type, or nutrition status from the combination.
One point is not a growth trend
This page describes measurements recorded on one date. One result cannot calculate growth velocity or show a pattern over time. If you have a second dated measurement, use the Growth Velocity Calculator. Changes in equipment, posture, or measurement method can affect any comparison between dates.
The age-2 handoff
In U.S. clinical settings, CDC recommends WHO growth standards from birth to age 2 and CDC growth charts beginning at age 2. The measurement also changes from recumbent length while lying down to standing height. A percentile may therefore change when both the chart and measurement method change; that change does not automatically represent a true growth problem. This site does not convert lying length to standing height.
If a result surprises you
- Confirm the birth and measurement dates.
- Confirm the selected units.
- Confirm that height and weight were entered in the correct fields.
- Repeat the measurement with consistent technique.
- Compare with previous dated records when available.
- Discuss a persistent concern with an appropriate healthcare professional.
Worked example
A boy born 2007-10-01 and measured 2011-11-15 is 1,506 days old: 4 years, 1 month, and 14 days. At 105.4 cm and 16.9 kg, height is about the 70.7th percentile, weight is about the 58th percentile, and BMI is 15.2 at about the 35.9th percentile. The CDC screening category is Healthy weight range.
The percentiles differ because stature, body weight, and BMI answer different questions. The numbers do not contradict one another, and this single dated result cannot establish a growth trend.
How the calculations work
Exact elapsed age selects the CDC reference for the chosen sex chart. Standing height and weight use the CDC 2000 stature-for-age and weight-for-age LMS references. When both measurements are present, BMI is compared with the CDC BMI-for-age reference, including the 2022 Extended BMI method where applicable. Formula details and source files are documented in the Methodology.
Limitations
- Results are reference comparisons, not diagnoses.
- One measurement does not establish a growth trend.
- Measurement technique and data-entry accuracy affect the result.
- The page does not predict adult height.
- It does not automatically select a clinical chart for an individual child.
- It does not recommend treatment.
References
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Helpful context
Frequently asked questions
Can I enter only height or only weight?
Yes. Height alone produces a height-for-age percentile, and weight alone produces a weight-for-age percentile. BMI-for-age is calculated only when both height and weight are entered.
Why are height, weight, and BMI percentiles different?
They use different inputs and answer different questions. Each percentile is a position in its own age- and sex-specific reference distribution, so the three numbers do not need to match.
Is weight percentile the same as BMI percentile?
No. Weight-for-age does not account for height and is not a weight-status category. BMI relates weight to height and is then compared by age and sex.
Can one result show a growth trend?
No. This page reviews measurements from one date. A trend or growth-velocity calculation requires at least two accurate measurements with dates.
Why did the result change after remeasuring?
Differences in posture, clothing, equipment, dates, units, or rounding can affect a result. Repeat the measurement with consistent technique before comparing it with earlier records.
What age is this calculator for?
It is for children from the second birthday through age 19, ending the day before the 20th birthday.
What should I use for a child under 2?
Use the WHO Baby Growth Calculator from birth through the day before the second birthday. It uses recumbent length rather than standing height.
Does a percentile diagnose a health problem?
No. Height, weight, and BMI percentiles are reference comparisons. Growth charts and BMI screening categories are not intended to diagnose a condition by themselves.
Does this site save my child’s measurements?
No. Calculator inputs are processed in your browser and are not saved as a child health record or sent to an external calculation service.