The fertility window estimator
Enter the first day of your last period and your usual cycle length. You will see an estimated fertile window for this cycle, with a plain explanation of what it can and cannot tell you.
This is a calendar estimate, not a test of ovulation or fertility. Cycles can shift, and a doctor can help if timing feels unclear. Your answers stay on this page unless you ask us to prepare a WhatsApp report.
The number of days from the start of one period to the start of the next. Around 28 is average.
Enter the first day of your last period to see your estimate.
Prefer to talk it through? Browse the free tools or book a consultation.
You do not have to figure this out alone.
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, 20+ years in practice
- A real doctor
- Private by design
- From anywhere in the world