Baby Age Calculators
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Use exact calendar dates for age, completed weeks for seven-day intervals, and corrected age only when prematurity makes that comparison relevant.
Choose a baby-age tool
Baby Age CalculatorCalculate a baby’s exact calendar age, completed weeks and total days with explicit date conventions.Corrected Age CalculatorEstimate corrected age for a baby born early from chronological age and gestational weeks at birth.Baby Formula CalculatorEstimate daily and per-feed formula volume from the AAP average weight rule while preserving responsive-feeding and product-mixing instructions.
Weeks are not months
Four weeks is 28 days. Calendar months vary from 28 to 31 days, so the same interval should be reported with its convention.
Feeding safety
The formula-volume tool remains held pending clinical review. It must never change mixing ratios or replace hunger cues and pediatric advice.
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