배란일 계산기
마지막 생리 시작일과 평균 주기로 배란일과 가임기를 추정합니다. 교육용 추정이며 의료 조언이 아닙니다.
기본값은 내 지역입니다. 다른 척도와 비교하려면 전환하세요.
Assumes a typical ~14-day luteal phase (ovulation ≈ cycle length − 14). Luteal length can vary by a few days between people and cycles.
From the first day of one period to the day before the next. Typical range about 21–45 days.
결과
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추정 배란일
Enter the first day of your last period
Educational estimate
교육용 달력 추정일 뿐이며 의료 조언이 아닙니다. 불규칙 주기·PCOS·난임 치료 시 의사와 상담하세요.
공식
Ovulation day ≈ LMP + (cycle length − 14)Fertile window ≈ ovulation − 5 days through ovulation dayNext period ≈ LMP + cycle lengthEstimated due date (if conception on ovulation) ≈ ovulation + 266 daysAssumes a typical ~14-day luteal phase; individual luteal length varies
계산 방법
- Enter the first day of your last menstrual period (LMP).
- Set your average cycle length (default 28; typical range about 21–45 days).
- Read the estimated ovulation date (primary result).
- Check the fertile window, next period, cycle day of ovulation, and optional due-date estimate.
- Treat results as a guide only — confirm with a clinician if cycles are irregular or you are in treatment.
자주 묻는 질문
How is ovulation estimated?
Calendar methods place ovulation about 14 days before the next period. With your average cycle length C, that is LMP + (C − 14). The fertile window is about the five days before ovulation through ovulation day, because sperm can live up to ~5 days and the egg about a day.
Is this medical advice or a fertility diagnosis?
No. This is an educational calendar estimate only. It cannot confirm ovulation, diagnose infertility, or replace LH strips, ultrasound, or a clinician. Seek medical care for irregular cycles, PCOS, endometriosis, or fertility treatment.
What if my cycle is irregular or I have PCOS?
Calendar estimates work best with fairly regular cycles. Large cycle-to-cycle swings, PCOS, recent hormonal contraception, breastfeeding, or perimenopause make the dates unreliable. Track symptoms or use ovulation tests and discuss planning with a clinician.
Why is the luteal phase fixed at 14 days?
After ovulation, the time until the next period is often the steadiest part of the cycle and averages about two weeks in many people. Teaching materials and ACOG-style fertility-awareness explanations therefore use ~14 days before the next period as a simple rule of thumb. Your own luteal length can be a few days shorter or longer.
How does this relate to the pregnancy due-date calculator?
If conception happens on the estimated ovulation day, adding 266 days gives an estimated due date (the same convention as dating from conception). For full pregnancy dating — including LMP + 280, IVF transfers, gestational age and leave dates — use the pregnancy due-date calculator.