Corrected Age Calculator
Calculate a preterm baby's chronological and corrected age from birth date and gestational age at birth.
출산예정일(40주): 2026.09.29 — 이날이 교정 나이 0일의 기준입니다
계산 내역
결과 공유
⚠️ 반드시 확인하세요
- 교정 나이는 재태 37주 미만 미숙아(이른둥이)의 성장·발달 평가에 사용하며, 통상 만 2세(교정 24개월)까지 적용합니다(대한소아청소년과학회·미국소아과학회 기준).
- 예방접종은 교정 나이가 아닌 실제 나이(출생일 기준)로 접종하는 것이 원칙입니다.
- 성장곡선·발달 이정표(뒤집기, 앉기, 걷기 등)는 교정 나이 기준으로 평가하세요.
- 이 결과는 참고용입니다. 발달 지연이 걱정되면 소아청소년과 진료를 받으세요.
Overview
The Corrected Age Calculator computes both the chronological age (from birth date) and the corrected age (from the due date) of a preterm baby born before 37 weeks of gestation. Corrected age is the age your baby would be if born at full term (40 weeks), and it is the clinical standard for evaluating growth charts and developmental milestones in preterm infants. Both the Korean Pediatric Society and the American Academy of Pediatrics recommend using corrected age until about 2 years (24 months corrected).
Formula
Prematurity offset (days) = 280 days (40 weeks) − gestational age at birth (weeks×7 + days) Due date = birth date + offset Corrected age = today − due date (calendar years/months/days) Chronological age = today − birth date e.g., born at 32w0d → offset 8 weeks (56 days); a 6-month-old is about 4 months 5 days corrected
How to Use
- 1Select the baby's birth date.
- 2Enter the gestational age at birth in weeks (e.g., 32).
- 3Choose the extra days (0–6) for a more precise result.
- 4Check the chronological age, corrected age, prematurity offset, and the original due date (corrected day 0).
Tips
- ✔Use corrected age for growth charts and developmental milestones (rolling, sitting, walking).
- ✔Vaccinations follow chronological age (birth date), not corrected age.
- ✔Corrected age is typically used until 24 months corrected; switch to chronological age afterwards.
- ✔Babies born at 37 weeks or later are full term and do not need age correction.
FAQ
Q. Why is corrected age needed?
A preterm baby starts development earlier than full-term peers. A baby born at 32 weeks arrived 8 weeks before the 40-week due date, so at 6 months of chronological age their expected development matches roughly a 4-month-old full-term baby. Corrected age prevents mislabeling normal preterm development as delayed.
Q. Until when should corrected age be used?
Pediatric societies, including the American Academy of Pediatrics, recommend using corrected age until about 2 years (24 months corrected), by which time most preterm children have caught up. For very low birth weight infants, clinicians may extend this to age 3.
Q. Do vaccinations follow corrected age?
No. Immunizations are scheduled by chronological age (from the actual birth date), not corrected age. Medically stable preterm infants follow the same vaccination schedule as full-term infants, though some vaccines (e.g., hepatitis B) may be adjusted for birth weight — consult your pediatrician.
Q. What if I don't know the exact gestational age?
The gestational age at birth is recorded in the maternity handbook, birth certificate, or NICU discharge summary, usually as weeks plus days (e.g., 32w4d). Entering the extra days improves accuracy. If unavailable, ask the delivery hospital or your pediatric clinic.
Related Calculators
BMI Calculator
Check your body mass index (BMI) and weight status.
BMR Calculator
Calculate your basal metabolic rate and daily calorie needs.
Water Intake Calculator
Calculate daily recommended water intake based on weight and activity.
Body Fat Calculator
Estimate body fat percentage using the US Navy method.
Ideal Weight Calculator
Calculate ideal weight range based on height and gender.
Target Heart Rate Calculator
Calculate target heart rate zones by exercise intensity.