Obstetrics · Growth

Birth Weight Centile Calculator

See where a baby's birth weight sits on the growth curve for their exact gestational age and sex, at delivery between 33+0 and 42+6 weeks.

Delivery details

Please enter a birth weight between 300 g and 6500 g.
Z-score
Median weight, this gestation
−2 SD (~2nd)−1 SD (~16th)Median (50th)+1 SD (~84th)+2 SD (~98th)
Estimate only. A single birth weight centile does not, by itself, diagnose a growth problem — it is one part of the overall clinical picture, alongside the pregnancy's growth trajectory and the baby's wellbeing. Please discuss this result with Dr McCaffrey or your paediatric team.
Reference: Nicolaides KH, Wright D, Syngelaki A, Wright A, Akolekar R. Fetal Medicine Foundation fetal and neonatal population weight charts — implemented here using the University of Oxford INTERGROWTH‑21st international newborn weight standard (Villar J et al, Lancet 2014), 33+0–42+6 weeks.