Estimate your ovulation day and fertile window with our free, private ovulation calculator. Enter your last period date and average cycle length.
We estimate ovulation as roughly 14 days before your next expected period and identify the fertile window — the 5 days before plus ovulation day itself.
Your peak fertility falls in the 2 to 3 days before ovulation. Sex during this window gives the highest chance of conception.
Combine the calculator with basal body temperature tracking, cervical mucus checks and LH ovulation tests for best accuracy.