Pink Mom MathWHO vs CDC Baby Growth Charts: Which Should You Use?
When you look up your baby's growth percentile, the chart you use matters. The World Health Organization (WHO) and the Centers for Disease Control (CDC) publish separate growth charts based on different populations and methodologies. Here is what each chart measures, who it is designed for, and when to use which.
What Are WHO Growth Charts?
The WHO growth charts were published in 2006 based on the Multicentre Growth Reference Study (MGRS), which followed approximately 8,500 children from birth to age 5 across six countries (Brazil, Ghana, India, Norway, Oman, and the United States). All children in the study were breastfed, lived in environments that did not limit growth, and received standard pediatric care.
Because the study selected for optimal growing conditions, WHO charts represent how children should grow — a prescriptive standard, not just a description of how children happen to grow in one country. The charts cover birth to age 5 and include weight-for-age, length/height-for-age, weight-for-length/height, and BMI-for-age.
What Are CDC Growth Charts?
The CDC growth charts were published in 2000 and are based on national survey data from the United States (primarily NHANES surveys from the 1960s through 1990s). The reference population includes both breastfed and formula-fed infants, reflecting the actual growth patterns of American children during that period.
CDC charts describe how children actually grew — a descriptive reference, not a standard for optimal growth. They cover birth to age 20 and include the same anthropometric measures as WHO charts, plus additional measures for older children and adolescents.
Key Differences at a Glance
| Feature | WHO Charts | CDC Charts |
|---|---|---|
| Type | Growth standard (prescriptive) | Growth reference (descriptive) |
| Population | 6 countries, breastfed, optimal conditions | US national surveys, mixed feeding |
| Age range | Birth to 5 years | Birth to 20 years |
| Recommended for (US) | Children under 2 years | Children ages 2-20 years |
| Breastfeeding impact | Designed for breastfed babies | May overdiagnose slow growth in breastfed babies |
Which Chart Should You Use?
In the United States, both the AAP (American Academy of Pediatrics) and the CDC recommend:
- Under age 2: Use the WHO growth charts. These better reflect healthy breastfed infant growth patterns and are less likely to trigger unnecessary concern about normal growth deceleration that occurs when a breastfed baby follows a different trajectory than formula-fed infants.
- Ages 2-20: Use the CDC growth charts. WHO charts only go to age 5, and the CDC charts provide continuous tracking through adolescence.
Our baby growth percentile calculator supports both WHO and CDC charts, automatically selecting the appropriate one based on your child's age — or letting you switch between them for comparison.
Why the Distinction Matters for Breastfed Babies
Breastfed babies typically gain weight rapidly in the first 3-4 months, then grow more slowly compared to formula-fed babies from 4-12 months. On CDC charts (which include formula-fed babies in the reference population), this natural deceleration can make a breastfed baby appear to be "falling off the curve" — potentially triggering unnecessary supplementation recommendations.
WHO charts were specifically built from breastfed babies, so this normal growth pattern is already reflected in the curves. A breastfed baby tracking along a consistent WHO percentile is growing as expected. For more on interpreting growth patterns, see our guide on baby growth percentiles explained.
When to Talk to Your Pediatrician
Regardless of which chart you use at home, your pediatrician tracks your child's growth at every well-child visit. Bring up growth concerns if you notice your child crossing two or more major percentile lines (e.g., dropping from the 50th to below the 10th) over several months. A single measurement that looks low or high is less important than the overall trend. Head circumference tracking is equally important — use our head circumference calculator to check between visits.