Baby & Parenting Calculators

APGAR Score Calculator

Calculate a newborn's APGAR score from Appearance, Pulse, Grimace, Activity, and Respiration, with the full scoring criteria and interpretation table.

Baby Age in Months Calculator

Calculate a baby's precise age in months, weeks, and days from a birth date using calendar-aware math, useful for vaccine and milestone scheduling needs.

Baby Growth Percentile Calculator

Estimate a baby's length or height percentile for age and sex using a simplified WHO growth standards approximation, with a median reference table shown.

Baby Sleep Schedule Calculator

Look up recommended total sleep and typical nap count by age band from newborn through preschool age, based on standard pediatric sleep guidelines.

Baby Weight Percentile Calculator

Estimate a baby's weight percentile for age and sex using a simplified WHO growth standards approximation, with a full reference table of median weights.

Breastfeeding Frequency Calculator

Look up recommended breastfeeding frequency and the resulting approximate interval between feeds by age band, from newborn through 12 months old.

Child Height Predictor Calculator

Predict a child's adult height from both parents' heights using the mid-parental height method, with a worked example and likely height range shown.

Diaper Usage Calculator

Estimate diaper usage over any number of days based on age-appropriate daily ranges, from newborn through toddler, with full weekly totals included.

Due Date Calculator

Estimate a pregnancy due date from the last menstrual period using Naegele's Rule, with current gestational age and trimester milestones fully explained.

Formula Feeding Calculator

Estimate daily and per-feed formula amounts from a baby's weight and feeding frequency, using the standard 2.5 oz per pound guideline with a worked example.

Tracking Development Without the Guesswork

Pediatric care leans heavily on percentiles and standardized schedules — a baby's weight and height are compared against WHO or CDC growth charts, not a fixed number, and feeding and sleep needs shift substantially month to month in the first year. These calculators apply the same reference standards and formulas used in pediatric checkups, so parents can check numbers between appointments.

Popular Baby & Parenting Calculators

Ten tools follow a baby from due date through the first years:

  • Due Date Calculator — estimates delivery date from last menstrual period or conception date.
  • Baby Growth Percentile Calculator — compares weight or length against standard growth charts for age.
  • Baby Sleep Schedule Calculator — suggests age-appropriate nap and night sleep totals as needs change over the first year.
  • Child Height Predictor Calculator — estimates adult height range from parental heights.
  • Breastfeeding Frequency Calculator — estimates expected feeding intervals based on age and weight.

Why Percentiles Matter More Than Raw Numbers

A baby's weight or height in isolation says little — what pediatricians track is the percentile curve over time, since a baby steadily tracking along the 25th percentile is generally healthier than one that suddenly drops from the 60th to the 30th, even though the second baby might still weigh more in absolute terms. Growth percentile calculators exist to make that comparison accessible between well-child visits, though any sudden shift in percentile trend is worth discussing with a pediatrician rather than diagnosing from a calculator alone.

Frequently Asked Questions

Is a due date calculator ever exact?
No — it estimates a probable delivery window; only about 4% of babies arrive on the exact estimated date, with most arriving within two weeks of it.

Do formula-fed and breastfed babies follow the same growth charts?
The WHO growth standard is based on breastfed infants as the norm, and some pediatricians use CDC charts (based on a broader feeding mix) instead, so the "right" chart can depend on feeding method and region.

Explore More

Tracking a pregnancy before the due date arrives? See the Pregnancy Calculators, or check nutrition needs in the Nutrition Calculators.