Is your baby growing
on track?
Free, clinically accurate infant growth percentile calculator. Interactive weight and height charts with WHO and CDC standards, growth spurt indicators, corrected age for preemies, and a printable pediatrician report.
More than a percentile number.
Competitor tools show you a number. We show you the full picture — with charts, context, and clinical guidance your pediatrician will recognise.
Interactive growth charts
Full WHO/CDC percentile band charts (P3–P97) with your baby plotted as a live dot. Hover for exact values at any age.
Growth spurt detection
Automatically flags typical growth spurt windows (3 weeks, 6 weeks, 3 months, etc.) and explains signs to expect.
Corrected age for preemies
Born before 37 weeks? Enter gestational age and all percentiles automatically adjust — a feature most tools skip.
Multi-child dashboard
Track siblings or compare growth over multiple visits. All data stays in your browser — nothing sent to our servers.
Printable PDF report
Generate a clean, formatted report to bring to your next pediatrician appointment — complete with charts and percentiles.
WHO or CDC, your choice
Toggle between WHO (recommended for under 2 years) and CDC (used by US pediatricians) with a plain-English explanation of when to use each.
Standards that fit your child's background
Used in 180+ countriesGrowth norms can vary by ethnicity and geography. The WHO Multicentre Growth Reference Study was designed specifically to reflect global diversity — data was collected from children in 6 countries across 4 continents (Brazil, Ghana, India, Norway, Oman, and the United States) who were raised under optimal healthy conditions. This makes WHO charts the most globally relevant standard, particularly if your family background differs from the historically US-centric CDC data. Our tool makes it easy to toggle between both, so you always use the right reference for your child's context.
Infant Growth Percentile Calculator.
Enter your baby's measurements and location to see percentiles on the most appropriate growth chart for your region — with interactive curves, growth spurt indicators, and a printable report.
Weight-for-age
Height-for-age
What do these numbers mean?
Multi-child dashboard.
No saved measurements yet
Calculate your baby's percentiles above, then click "Save to Dashboard" to track growth over time.
Open calculatorAll data is stored only in your browser's localStorage. Nothing is sent to any server.
WHO vs CDC: which standard should you use?
The World Health Organization (WHO) chart describes how children should grow when their environment supports healthy development. It was built from children in 6 countries raised under optimal conditions (breastfed, non-smoking households, etc.).
The CDC chart describes how US children historically grew in the 1970s–90s, including formula-fed babies. It is a reference, not a standard.
Use WHO when…
- Infant is under 2 years old
- Baby is breastfed
- You want the global standard
- Comparing to international peers
Use CDC when…
- Child is 2–20 years old
- Your US pediatrician requests it
- Tracking BMI in school-age children
- Comparing to US national norms
Typical growth spurt timeline.
Growth spurts are brief periods of rapid physical and developmental change. Knowing when they happen helps you prepare for fussiness, sleep disruption, and appetite changes.
3 weeks old
Duration: 1–3 days
6 weeks old
Duration: 2–3 days
3 months old
Duration: 3–5 days
6 months old
Duration: 3–5 days
9 months old
Duration: 3–5 days
12 months old
Duration: 4–7 days
18 months old
Duration: 5–7 days
2 years old
Duration: 1 week
Not every baby follows the same schedule. These are typical windows, not rules. Some babies show no obvious signs; others have more pronounced spurts. If you're concerned about your baby's growth pattern, a visit to your pediatrician is always worthwhile.
Corrected age matters for preemies.
A baby born at 32 weeks has spent 8 fewer weeks developing in the womb than a full-term baby. Comparing them to the same-age growth chart would make them appear small — even if they're growing perfectly for their developmental stage.
Corrected age (also called adjusted age) subtracts the weeks of prematurity from the chronological age. For example, a 6-month-old born 8 weeks early has a corrected age of about 4 months.
Most clinicians use corrected age for growth chart comparisons until the child is 2–3 years old, when premature babies typically "catch up" to their full-term peers.
Try the corrected age calculatorCorrected age formula
chronological_age = 6 months
gestational_age = 32 weeks
weeks_premature = 40 − 32 = 8 weeks
corrected_age = 6 months − (8 ÷ 4.33) weeks
= ~4.1 months
Charts compare your baby to 4-month-old norms, not 6-month-old norms.
Frequently asked questions.
Track your baby's growth today.
Free, accurate, and private. No sign-up required.
Infant Weight Height Percentile Calculator — Complete Guide
Our free infant weight height percentile calculator is the most comprehensive growth-tracking tool available online for parents, caregivers, and healthcare professionals. Whether you need to check your child's infant weight percentile, monitor infant height percentile, calculate average infant weight by age, or identify an upcoming infant growth spurt, this tool delivers clinically accurate answers in seconds — backed by official WHO and CDC growth chart standards.
What Is an Infant Percentile?
A percentile tells you how your baby's measurements compare to other children of the same age and sex. If your infant boy is at the 65th percentile for weight, it means 65% of baby boys his age weigh less. Percentiles from the 3rd to the 97th are all within the healthy range — what matters most is whether your child's infant weight gain and infant height gain follow a consistent curve over time. Our infant weight tracker and infant height tracker make it easy to log multiple measurements and visualise that curve.
WHO vs CDC: Which Infant Growth Chart Calculator Should You Use?
The WHO infant growth chart calculator and the CDC infant percentile calculator use different reference populations. The WHO standard was built from children in six countries raised under optimal healthy conditions, making it the most globally representative chart — used in over 180 countries for children under 2. The CDC growth chart is based on how US children grew in the 1970s–90s, including formula-fed babies, and is widely used by US pediatricians for children aged 2–20.
Our infant growth percentile calculator by country and by race features let you apply the chart that best fits your child's background. For families outside the US, the WHO standard is almost always more appropriate. Toggle between WHO and CDC instantly with a single click.
Infant Boy & Infant Girl Weight and Height Percentile Calculator
Growth norms differ between sexes. Our infant boy weight percentile calculator applies the male WHO/CDC reference curves, while the infant girl weight percentile calculator uses the female curves. The same separation applies to height: the infant boy height percentile and infant girl height percentile are plotted on sex-specific charts, with full percentile band overlays (P3, P10, P25, P50, P75, P90, P97). This also extends to toddlers — the toddler boy growth chart calculator and toddler girl growth chart calculator cover ages 2–5 years seamlessly.
Premature Baby Growth Percentile Calculator
Standard growth charts can produce misleading results for babies born before 37 weeks. Our premature baby growth percentile calculator automatically computes corrected (adjusted) age by subtracting the weeks of prematurity from the chronological age. This is available for both premature baby boy and premature baby girl measurements, covering the full range of gestational ages. Clinicians typically use corrected age until a child reaches 2–3 years, when most preemies have caught up to their full-term peers.
Infant Growth Spurts — Detection & Timeline
An infant spurt — or infant growth spurt — is a brief window of rapid physical development typically accompanied by increased feeding, disrupted sleep, and fussiness. Our infant growth chart calculator automatically highlights known spurt windows at 3 weeks, 6 weeks, 3 months, 6 months, and 9 months of age. Understanding when a baby spurt is likely helps parents respond confidently, rather than worrying that something is wrong. The same detection applies for toddler spurt windows through 24 months.
Track Baby Weight Gain Per Week & Generate Reports
Beyond single-point percentiles, this baby growth calculator lets you log multiple visits to track baby weight gain per week and average baby weight trends over time. A multi-child dashboard stores all measurements locally in your browser — no account, no data sent to our servers. When you're ready for your next appointment, generate a clean printable PDF report your pediatrician will recognise, complete with baby weight chart and baby height chart overlays on WHO or CDC grids.
Medical disclaimer: This infant weight height percentile calculator is provided for informational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always consult your child's pediatrician or healthcare provider with questions about your baby's growth, nutrition, or health.