Child · Growth
Child Growth Chart Plotter
Plot your child's growth across age and sex-specific centiles (WHO / CDC). Plus what centile bands mean, when to worry about drops or jumps, preterm correction, and the difference between weight, height, and head circumference charts.
Last reviewed 1 June 2026
Height & weight percentile (CDC LMS)
Child & teen growth chart — ages 2-20
Units
Sex assigned at birth
y
mo
cm
kg
Enter age, height and weight to see CDC percentiles.
What is a growth chart?
Reference chart plotting a child’s height, weight, head circumference, or BMI against age and sex. Compares to a reference population of healthy children.
- UK uses UK-WHO growth charts (WHO 0-4 years; UK 1990 data 4-18 years).
- US uses CDC charts (WHO under 2; CDC 2-20 years).
- Healthcare workers plot at routine visits.
- Centiles (3rd, 25th, 50th, 75th, 97th) show how child compares.
What do centiles mean?
- 50th centile = median — half weigh more, half less.
- NOT “optimal” — just average for reference population.
- Healthy children fall mostly between 3rd and 97th.
- Most concerning: CROSSING centiles, not where you are.
Child on 25th tracking that line = healthy. Child on 90th tracking that line = healthy. Child jumping from 50th to 5th = potentially concerning.
WHO vs CDC vs UK-WHO charts
- WHO 2006: healthy, exclusively breastfed babies from 6 countries. How children SHOULD grow under optimal conditions.
- CDC 2000: US reference sample including formula-fed. Describes growth in US population.
- UK-WHO: hybrid (WHO 0-4y, UK 1990 4-18y).
Choice doesn’t usually change clinical decisions but interpretations differ slightly especially first year.
Why is my baby dropping centiles?
Some dropping is normal physiological:
- Breastfed babies often drop centiles around 4-6 months on CDC charts (less so on WHO).
- Slight centile shift across one visit can be measurement error.
Concerning patterns:
- Crossing 2+ major centile lines downward over months.
- Persistently below 3rd centile.
- Weight loss or no gain after first 2 weeks.
- Reduced feeding / unwell appearance.
Investigate: feeding adequacy, illness, chronic condition. GP/HV review.
What is faltering growth?
Older term “failure to thrive” now called faltering growth per NICE NG75. Defined as:
- Weight CROSSING TWO OR MORE major centile lines DOWNWARD.
- Weight persistently below 0.4th centile.
- Weight-for-height below 2nd centile.
Causes: feeding difficulty (~30%); inadequate intake; vomiting / reflux / CMPA / coeliac; malabsorption; chronic illness; psychosocial; genetic syndromes. Assessment: full history, feeding observation, growth review, basic bloods, paediatric input.
How often should babies be weighed?
UK NHS: every well-baby visit and immunisation. NICE NG194 advises AGAINST routine weighing more than once a month after 2 weeks unless concerns (over-frequent weighing causes parental anxiety without changing outcomes).
US AAP: 1-2 weeks, 2 months, 4 months, 6 months, 9, 12, 15, 18, 24 months.
Corrected age for preterm
Chronological age minus weeks of prematurity = corrected age. Born at 32 weeks (8 weeks early), at 6 months chronological = 4 months corrected. Use until ~2 years (some preterm catch up by 1y; very preterm may use corrected to 2-3y). After 2 years: chronological age suffices.
Different scenarios — what your chart shows
Scenario 1: 4-month-old breastfed, dropped from 50th to 25th weight
Often physiological (breastfed pattern on CDC charts). Check WHO chart (likely better tracking). Confirm good wet nappies, milestones, feeding well. Likely reassuring. Recheck in 4-6 weeks.
Scenario 2: 8-month-old crossed from 50th to 5th over 3 months
Concerning pattern. Faltering growth. Paediatric review — full feeding history, coeliac screen, IgA + TTG bloods, FBC, U&E, LFT, TSH, ferritin, vit D.
Scenario 3: 6-month-old, 97th centile weight, 75th centile length
Mismatch — weight relatively high for length. Worth feeding-pattern review. Often resolves as baby becomes more active. Not a problem if growing normally.
Scenario 4: 12-month-old former 30-week preterm
Use corrected age (10 months corrected). May still be small for chronological age but should be tracking own corrected curve. Most catch up by age 2.
Scenario 5: Toddler with constipation and slow weight gain
Coeliac screen, full thyroid screen, paediatric dietitian referral. Often constipation responds to first-line treatment AND weight improves once underlying issue addressed.
Red flags — consult GP / HV
- Weight crossing 2+ major centile lines downward over months.
- Weight persistently below 0.4th (UK) / 3rd (US) centile.
- Weight loss after first 2 weeks.
- Head circumference crossing centiles up or down.
- Significant difference between height and weight centiles.
- Signs of underlying illness.
- Not meeting developmental milestones.
- Family concern that something’s wrong.
Sources
- WHO. Child Growth Standards. 2006.
- CDC. Growth Charts. 2000.
- RCPCH. UK-WHO growth charts.
- NICE NG75. Faltering growth: recognition and management.
- NICE NG194. Postnatal care.
- Fenton TR, Kim JH. A systematic review and meta-analysis to revise the Fenton growth chart for preterm infants. BMC Pediatr 2013.
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Frequently asked questions
What is a growth chart?
A reference chart plotting a child's height, weight, head circumference, or BMI against age and sex. Compares child to a reference population of healthy children. UK uses UK-WHO growth charts (0-4 years WHO Child Growth Standards; UK 1990 data for 4-18 years). US uses CDC charts (WHO under 2; CDC 2-20). Healthcare workers plot at routine visits to monitor growth trend. Centiles (3rd, 25th, 50th, 75th, 97th lines) show how baby compares — most healthy children fall between 3rd and 97th.
What does '50th centile' mean?
50th = MEDIAN — half of healthy children weigh more, half less. Doesn't mean 'optimal' — just average for the reference population. Centiles are descriptive not prescriptive. CHILD on 25th centile and tracking that line = healthy. CHILD on 90th centile and tracking that line = healthy. CHILD jumping from 50th to 5th over a few months = potentially concerning. The CURVE matters, not the single point. Most concern about 'low' or 'high' centiles comes from misunderstanding this.
What's the difference between WHO and CDC growth charts?
WHO CHARTS (Child Growth Standards 2006): based on healthy, EXCLUSIVELY BREASTFED babies from 6 countries. Show how children SHOULD grow under optimal conditions. UK uses WHO 0-4 years. CDC CHARTS (2000): based on US reference sample including formula-fed; describes growth in US population. US uses CDC 2-20 years (and WHO under 2). UK-WHO charts: hybrid (WHO 0-4y, UK 1990 4-18y). Choice doesn't usually change clinical decisions but interpretations differ slightly especially first year.
Why is my baby dropping centiles?
Some 'dropping' is NORMAL physiological. BREASTFED babies often drop centiles around 4-6 months on CDC charts (formula-fed babies grew faster in CDC reference cohort) but tracking remains normal on WHO charts. SLIGHT CENTILE shift across one visit can be measurement error. CONCERNING patterns: crossing 2+ major centile lines downward over months; persistently below 3rd centile; weight loss or no gain; reduced feeding / unwell appearance. INVESTIGATE: feeding adequacy, illness, growth restriction in utero, chronic condition. Worth GP / HV review.
What's the difference between height, weight, and head circumference charts?
WEIGHT-FOR-AGE: most commonly tracked. Sensitive to feeding, acute illness, dehydration. LENGTH/HEIGHT-FOR-AGE: tracks linear growth; affected by chronic nutrition, genetics, chronic disease. HEAD CIRCUMFERENCE-FOR-AGE: tracks brain growth. Big in first 2 years. Small or large head + crossing centiles concerning (hydrocephalus, microcephaly investigations). WEIGHT-FOR-HEIGHT / BMI: reflects relative fatness. From age 2: BMI-for-age. CHRONIC undernutrition shows: low length first, then weight; chronic illness slows growth across all measurements.
What is 'failure to thrive' (FTT)?
Older term — now called 'FALTERING GROWTH' per NICE NG75. Defined as: weight CROSSING TWO OR MORE MAJOR CENTILE LINES DOWNWARD over months; weight persistently BELOW 0.4th CENTILE; weight-for-height below 2nd centile. Acute (under 3 months) vs chronic. CAUSES: feeding difficulty (~30%); inadequate intake; vomiting / reflux / cow's milk protein allergy / coeliac; malabsorption; chronic illness (cystic fibrosis, congenital heart disease); psychosocial; genetic syndromes. ASSESSMENT: full history, feeding observation, growth review, basic bloods, paediatric input.
My baby is in the 97th centile — is that concerning?
Not on its own. Many big babies are healthy big babies (genetic, family pattern). CONCERN if: rapid jump UP across centiles; weight much higher than height centile (overweight risk); maternal GDM during pregnancy (large-for-gestational-age + neonatal hypoglycaemia risk); endocrine cause (rare). Most 97th-centile babies are simply at the upper end of normal. WORKUP if rapid weight gain crossing lines: feeding history, family size pattern, screen for endocrine causes (rare). See /calculators/child-bmi for over-2 BMI assessment.
My baby is on the 3rd centile — is that concerning?
Not on its own. Many small babies are healthy small babies (genetic — small parents, family pattern, ethnicity). CONCERN if: crossing centiles DOWN; weight much lower than height centile (failing to grow); previous SGA at birth + not catching up; signs of malnutrition or chronic illness; signs of feeding difficulty. WORKUP: feeding observation, basic bloods (FBC, U&E, LFT, TSH, IgA + TTG for coeliac, ferritin, vitamin D); growth velocity over 3-6 months. Most 3rd centile children turn out to be constitutionally small but healthy.
How often should babies be weighed?
UK NHS pattern: every well-baby visit and immunisation appointment (birth, 5 days, 10-14 days, 8 weeks, 12 weeks, 16 weeks, 1 year). NICE NG194 specifically advises AGAINST routine weighing more than ONCE A MONTH after 2 weeks unless concerns (over-frequent weighing causes parental anxiety, doesn't change outcomes). US: typical AAP schedule at 1-2 weeks, 2 months, 4 months, 6 months, 9 months, 12 months, 15 months, 18 months, 24 months. EXTRA monitoring if growth concerns.
What is corrected age for preterm babies?
Adjustment for premature birth when interpreting growth and development. CHRONOLOGICAL AGE minus weeks of prematurity = corrected age. EXAMPLE: born at 32 weeks (8 weeks early), at 6 months chronological = 4 months corrected. USE CORRECTED AGE: on growth charts; for developmental milestones; until ~2 YEARS (some preterm-born children catch up by 1y; very preterm may use corrected to 2-3y). FENTON 2013 chart used for very-preterm infants until term-equivalent age. AFTER 2 years: usually chronological age suffices.
Can growth chart predict adult height?
Roughly. CHILD'S CENTILE around age 2-4 tends to predict adult-height centile. But more accurate predictors exist: MID-PARENTAL HEIGHT formula (see /calculators/child-height-predictor) — 95% confidence interval ±8.5 cm. BONE-AGE X-RAY in older children — paediatric endocrinology. INDIVIDUAL variation huge; many late bloomers and early developers throw off predictions. Don't predict too confidently — child's actual trajectory is what matters.
What about ethnicity-specific growth charts?
WHO 2006 charts use a multi-country sample (Brazil, Ghana, India, Norway, Oman, US Boston) showing GENETIC POTENTIAL is similar across ethnicities when environment is optimal — differences in actual growth largely reflect nutrition / health, not genetic differences. SOME COUNTRIES use national charts (UK 1990 data for older ages; Singapore-specific charts; specific tribal / national variants). For children from ethnicities historically underweight, ethnicity-adjusted thresholds for cardiometabolic risk apply (e.g. South Asian children's BMI cutoffs).
How do I read a growth chart at home?
PLOT: find child's age (x-axis) and measurement (y-axis); plot dot. CENTILE LINES (3rd, 5th, 10th, 25th, 50th, 75th, 90th, 95th, 97th) show where most children fall. INTERPRETATION: TRACK over time (multiple visits). NORMAL: tracking own centile or slowly crossing one line (max). CONCERNING: crossing 2+ major centile lines; below 0.4th (UK) or 3rd (US); above 99.6th (UK) or 97th (US). Bring queries to GP / HV. Don't obsessively chart at home — anxiety amplifies normal variation.
Why does my baby's weight drop after birth?
Newborn loses 5-7% of birth weight in first 3-5 days; up to 10% can be normal. WHY: passing meconium; losing extra-cellular fluid; mother's milk takes a few days to come in. RECOVERY by 10-14 days. WORRY: > 10% weight loss; weight not regained by 14 days; pale / lethargic / not feeding. See /calculators/newt-weight-loss for the specific NEWT weight-loss centile. NICE / Lullaby Trust track this carefully.
What red flags should I look for?
CONSULT GP / HV / paediatrician if: weight crossing 2+ major centile lines downward over months; weight persistently below 0.4th (UK) / 3rd (US) centile; weight loss after first 2 weeks; head circumference crossing centiles up or down; significant difference between height and weight centiles; signs of underlying illness (vomiting, diarrhoea, fevers, frequent infections); not meeting developmental milestones; family concern that something's wrong. TRUST your instinct.
How does this relate to other calculators on BumpBites?
Companion: /calculators/baby-percentile for the WHO 0-24 month calculator; /calculators/child-bmi for ages 2+; /calculators/child-height-predictor for adult height estimate; /calculators/newt-weight-loss for newborn weight-loss percentile; /calculators/fenton-growth for preterm-specific chart; /calculators/milestone-tracker for developmental tracking alongside growth.