See your estimated fertile days for this cycle. Takes about a minute.
Your details
The number of days from the start of one period to the start of the next. Around 28 is average.
Pick your last period's start date to see your window.
Live result
Your fertile window will appear here.
This is a calendar estimate, not a test of ovulation or fertility. Cycles can shift, and a doctor can help if timing feels unclear.
This window is calendar math based on your last period and your usual cycle length. Ovulation tends to happen about 14 days before the next period begins. The fertile window covers six days: the five days before ovulation through ovulation day.
Ovulation is not a fixed appointment. Stress, travel, illness and normal month-to-month variation can move it by a few days, so treat this window as a helpful guide rather than a rule.
Calendar estimates work best when cycles are fairly regular. If your cycle length changes a lot from month to month, the window here becomes less reliable, and a doctor can help you find better ways to read your body's timing.
A calculator can estimate, but only your body can confirm. Doctors use things like home LH kits, cervical mucus changes and sometimes a scan or blood test to know ovulation is actually happening.
Doctors usually suggest a check-up after about a year of trying if you are under 35, or after six months if you are 35 or older. Asking sooner is always reasonable if something feels off. A gynecologist can look at ovulation, cycle timing and partner factors together, without judgment.
Share what is going on, and a gynecologist will look at your whole picture. Clear answers, a calm plan, no judgment.
Dr. Geeta S K · Gynecologist, 11 years in practice
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