Loona Calculators
Planning a pregnancy? Enter the first day of your last period and your usual cycle length to estimate your ovulation day, your most fertile window and your next period.
Ovulation usually happens about 14 days before the next period, so it is estimated as: last period + cycle length − 14 days. The fertile window is the 5 days before ovulation plus ovulation day itself.
No. Cycles vary from month to month and estimates can be off by several days. Never rely on a calculator to prevent pregnancy.
If you conceive in this cycle, an estimated due date of ovulation + 266 days. It is an estimate only — your doctor will confirm with scans.