月經週期計算器

分析月經週期並預測排卵日和受孕期

First day of last period

Average cycle length (days)

Estimated next period

2026年11月28日

Estimated ovulation

2026年11月14日

Estimated fertile window

2026年11月9日 – 2026年11月15日

This is a calendar estimate. Ovulation can vary from cycle to cycle and estimates are less reliable with irregular cycles, lactation, perimenopause, illness, or medicines. Do not use it for contraception, pregnancy confirmation, or infertility diagnosis.

Seek medical advice for a sudden cycle change, no period for 3 months when not pregnant, very heavy bleeding, fainting, or severe pelvic pain.